Vendor beacon firmware as a submodule with a one-shot hex build/export (#38)

Add hci_uart_beacon as the firmware/ git submodule (pinned to master 52d034e,
which includes the LFXO crystal clock fix) and formalize the firmware ->
src/openocd/merged.hex handoff so the deployed image is reproducible and
traceable:

- src/openocd/update_firmware.sh: build and export the sysbuild merged.hex.
  `--build` is a one-shot — it configures AND builds the sysbuild image via
  `nrfutil toolchain-manager launch` (no manual env setup), reading BOARD and
  the conf/overlay files straight from firmware/CMakePresets.json, then copies
  merged.hex to src/openocd/ and records provenance in merged.hex.version.
  Without --build it just re-exports an existing build. Refuses a zephyr.hex
  fallback. --preset / --ncs-version override the defaults.
- src/openocd/merged.hex: built from firmware 52d034e with the
  build_nrf54_radio0_radio1 preset (prj.conf + iso.conf;clk.conf +
  bl54l15_radio0_radio1.overlay); the committed hex matches the submodule pin
  and reproduces bit-for-bit from `update_firmware.sh --build`. LFCLK now runs
  from the 32.768 kHz crystal (was the internal RC oscillator).
- README: documents the submodule, the committed-artifact model (devices flash
  the prebuilt hex, no toolchain needed), and the one-shot rebuild flow.
- CLAUDE.md: now tracked in-repo; its deploy rsync gains --exclude='firmware/'
  so the ~GB NCS build tree never reaches devices (they only need the hex).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Reviewed-on: #38

.gitignore

@@ -13,6 +13,7 @@ auracast.egg-info/
 
 # Ignore virtual environment data
 venv/
+.venv/
 env/
 
 # Ignore any IDE configurations or project-specific metadata
@@ -53,3 +54,9 @@ src/scripts/temperature_log*
 
 src/auracast/server/recordings/
 src/auracast/server/led_settings.json
+
+
+# Dante license files
+*.lic
+src/dep/dante_package/dante_data/activation/device.lic
+src/dep/dante_package/dante_data/activation/manufacturer.cert

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "firmware"]
+	path = firmware
+	url = ssh://git@gitea.summitwave.work:222/auracaster/hci_uart_beacon.git

CLAUDE.md

@@ -0,0 +1,60 @@
+# CLAUDE.md
+
+Guidance for Claude Code when working in this repo.
+
+## Deploying to a beacon dev device
+
+Devices (e.g. **beacon29**) run the Auracast frontend + backend as systemd services.
+The deploy workflow is a **whole-tree rsync** of the local working copy onto the device,
+followed by re-running the service update script. The device's `.git` is pinned to an old
+commit while its files drift ahead, so `git status` on the device looks noisy — that is
+expected, do not try to "fix" it with `git pull`/checkout.
+
+### 1. Sync (laptop -> device)
+
+```bash
+rsync -avz \
+  --filter=':- .gitignore' \
+  --exclude='.git/' \
+  --exclude='firmware/' \
+  --exclude='src/dep/dante_package/bundle/' \
+  --exclude='src/dep/dante_package/dante_data/activation/' \
+  --delete \
+  /home/paul/Documents/bumble-auracast/ \
+  caster@beacon29.local:/home/caster/bumble-auracast/
+```
+
+- ⚠️ **NEVER delete or overwrite the Dante activation files/dir**
+  (`src/dep/dante_package/dante_data/activation/` — contains `device.lic`,
+  `manufacturer.cert`). It is per-device licensing and is unrecoverable if lost.
+  The `--exclude` rules above protect it (with `--delete`, excluded paths are left
+  untouched). Keep those excludes, and never use `--delete-excluded`.
+- Always **dry-run first** (`rsync -avzn ...`) and confirm there are no `deleting`
+  lines touching `activation/` or `bundle/` before doing the real sync.
+- Target by hostname. **beacon29 = `beacon29.local` (10.11.0.59).** Don't blindly reuse
+  IPs from old commands (an earlier example used `10.11.0.48`, a different device).
+- The `firmware/` submodule (nRF firmware source + ~GB nRF Connect SDK build tree) is
+  **excluded** — devices only need the committed `src/openocd/merged.hex`, which still
+  syncs. Rebuild the hex on the laptop with `src/openocd/update_firmware.sh`; never build
+  firmware on the device.
+
+### 2. Restart services on the device
+
+```bash
+ssh caster@beacon29.local '
+  export XDG_RUNTIME_DIR=/run/user/$(id -u)   # needed for the `systemctl --user` backend restart over SSH
+  cd ~/bumble-auracast
+  bash src/service/update_and_run_server_and_frontend.sh
+'
+```
+
+This restarts `dep.service`, `auracast-frontend.service` (system), and
+`auracast-server.service` (user). For a **frontend-only** change you can instead just
+`sudo systemctl restart auracast-frontend.service`. A benign
+`Failed to bring up Wired connection 2` line is normal when the 2nd ethernet port is
+unplugged.
+
+### 3. Verify
+
+- Frontend serves HTTPS: `curl -sk -o /dev/null -w "%{http_code}\n" https://beacon29.local/` → `200`.
+- `caster@beacon29.local` has passwordless SSH and passwordless sudo.

README.md

@@ -61,6 +61,43 @@ sudo ./provision_domain_hostname.sh <new_hostname> <new_domain>
 - If you have issues with mDNS name resolution, check for conflicting mDNS stacks (e.g., systemd-resolved, Bonjour, or other daemons).
 - Some Linux clients may not resolve multi-label mDNS names via NSS—test with `avahi-resolve-host-name` and try from another device if needed.
 
+## Beacon firmware (nRF54L15)
+
+The two nRF54L15 radios on a beacon are flashed with `src/openocd/merged.hex`
+(via `src/openocd/flash.sh`, driven by `src/auracast/server/system_update.sh`).
+
+- **Firmware source** lives in the `firmware/` git submodule (`hci_uart_beacon`).
+  Clone with submodules:
+  ```bash
+  git clone --recurse-submodules <repo>
+  # or, in an existing clone:
+  git submodule update --init firmware
+  ```
+- **`src/openocd/merged.hex` is a committed build artifact.** Beacon devices have no
+  nRF Connect SDK toolchain, so they flash this prebuilt hex directly — you do **not**
+  need the submodule or the toolchain just to deploy.
+- **To rebuild the firmware and refresh `merged.hex`** (requires the nRF Connect SDK
+  under `~/ncs`):
+  ```bash
+  git submodule update --init firmware
+  # optional: check out a different firmware commit inside firmware/
+  src/openocd/update_firmware.sh --build
+  git add firmware src/openocd/merged.hex src/openocd/merged.hex.version
+  ```
+  `--build` is a one-shot: it configures **and** builds the `build_nrf54_radio0_radio1`
+  sysbuild image from the checked-out firmware commit (via
+  `nrfutil toolchain-manager launch --ncs-version v3.0.2` → `west build --sysbuild`),
+  copies the resulting `merged.hex` into `src/openocd/`, and records provenance in
+  `src/openocd/merged.hex.version`. BOARD and the conf/overlay files are read straight
+  from `firmware/CMakePresets.json`, so it stays in sync with the nRF Connect VS Code
+  preset. Override with `--preset NAME` / `--ncs-version VER`. `merged.hex` is a
+  *sysbuild* output — the script refuses a plain `zephyr.hex` fallback.
+- **To just re-export** an already-built tree (no rebuild), run
+  `src/openocd/update_firmware.sh` with no `--build`.
+- **Deploy note:** the whole-tree rsync deploy must exclude the firmware tree
+  (`--exclude='firmware/'`) — devices only need the committed hex, not the GB-scale
+  toolchain / build tree.
+
 # record audio and save to file for debugging
 pw-record --target="AVIOUSB-8f6326 : 2:receive_Left" --rate=48000 --channels=1 --format=s24 /tmp/aes67_test.wav &
 RECORD_PID=$!

src/auracast/auracast_config.py

@@ -1,5 +1,11 @@
 from typing import List
-from pydantic import BaseModel
+from pydantic import BaseModel, field_validator
+
+# Discrete TX power levels (dBm) supported by the Nordic SoftDevice Controller
+# for the nRF radio PA. The HCI controller will clamp requested values to the
+# nearest supported step. The maximum is bounded by CONFIG_BT_CTLR_TX_PWR_*
+# in the hci_uart firmware (currently +8 dBm).
+TX_POWER_VALID = [8, 7, 6, 5, 4, 3, 2, 0, -4, -8, -12, -16, -20]
 
 # Define some base to hold the relevant parameters
 class AuracastQoSConfig(BaseModel):
@@ -28,13 +34,24 @@ class AuracastGlobalConfig(BaseModel):
     octets_per_frame: int = 40 #48kbps@24kHz # bitrate = octets_per_frame * 8 / frame len
     frame_duration_us: int = 10000
     presentation_delay_us: int = 40000
-    # TODO:pydantic does not support bytes serialization - use .hex and np.fromhex()
-    manufacturer_data: tuple[int, bytes] | tuple[None, None] = (None, None)
     # LE Audio: Broadcast Audio Immediate Rendering (metadata type 0x09)
     # When true, include a zero-length LTV with type 0x09 in the subgroup metadata
     # so receivers may render earlier than the presentation delay for lower latency.
     immediate_rendering: bool = False
     assisted_listening_stream: bool = False
+    # Bluetooth advertising TX power for this radio in dBm (per advertising set).
+    # Sent through HCI_LE_Set_Extended_Advertising_Parameters; the SDC clamps to
+    # nearest supported hardware step and propagates to primary/secondary adv,
+    # the periodic advertising train and the BIS ISO PDUs.
+    advertising_tx_power: int = 8
+
+    @field_validator('advertising_tx_power')
+    @classmethod
+    def _snap_tx_power(cls, v: int) -> int:
+        # Snap to the nearest supported discrete step in TX_POWER_VALID.
+        if v in TX_POWER_VALID:
+            return v
+        return min(TX_POWER_VALID, key=lambda s: abs(s - v))
 
 # "Audio input. "
 # "'device' -> use the host's default sound input device, "
@@ -62,7 +79,7 @@ class AuracastBigConfigDeu(AuracastBigConfig):
     name: str = 'Hörsaal A'
     language: str ='deu'
     program_info: str = 'Vorlesung DE'
-    audio_source: str = 'file:./testdata/wave_particle_5min_de.wav'
+    audio_source: str = 'file:./testdata/wave_particle_5min_de.lc3'
 
 class AuracastBigConfigEng(AuracastBigConfig):
     id: int = 123
@@ -70,7 +87,7 @@ class AuracastBigConfigEng(AuracastBigConfig):
     name: str  = 'Lecture Hall A'
     language: str ='eng'
     program_info: str = 'Lecture EN'
-    audio_source: str  = 'file:./testdata/wave_particle_5min_en.wav'
+    audio_source: str  = 'file:./testdata/wave_particle_5min_en.lc3'
 
 class AuracastBigConfigFra(AuracastBigConfig):
     id: int = 1234
@@ -79,7 +96,7 @@ class AuracastBigConfigFra(AuracastBigConfig):
     name: str  = 'Auditoire A'
     language: str ='fra'
     program_info: str = 'Auditoire FR'
-    audio_source: str  = 'file:./testdata/wave_particle_5min_fr.wav'
+    audio_source: str  = 'file:./testdata/wave_particle_5min_fr.lc3'
 
 class AuracastBigConfigSpa(AuracastBigConfig):
     id: int =12345
@@ -87,7 +104,7 @@ class AuracastBigConfigSpa(AuracastBigConfig):
     name: str  = 'Auditorio A'
     language: str ='spa'
     program_info: str = 'Auditorio ES'
-    audio_source: str  = 'file:./testdata/wave_particle_5min_es.wav'
+    audio_source: str  = 'file:./testdata/wave_particle_5min_es.lc3'
 
 class AuracastBigConfigIta(AuracastBigConfig):
     id: int =1234567
@@ -95,7 +112,7 @@ class AuracastBigConfigIta(AuracastBigConfig):
     name: str  = 'Aula A'
     language: str ='ita'
     program_info: str = 'Aula IT'
-    audio_source: str  = 'file:./testdata/wave_particle_5min_it.wav'
+    audio_source: str  = 'file:./testdata/wave_particle_5min_it.lc3'
 
 
 class AuracastBigConfigPol(AuracastBigConfig):
@@ -104,7 +121,7 @@ class AuracastBigConfigPol(AuracastBigConfig):
     name: str  = 'Sala Wykładowa'
     language: str ='pol'
     program_info: str = 'Sala Wykładowa PL'
-    audio_source: str  = 'file:./testdata/wave_particle_5min_pl.wav'
+    audio_source: str  = 'file:./testdata/wave_particle_5min_pl.lc3'
 
 
 class AuracastConfigGroup(AuracastGlobalConfig):

src/auracast/multicast.py

@@ -49,6 +49,7 @@ import bumble.transport
 import bumble.utils
 from bumble.device import Host, AdvertisingChannelMap
 from bumble.audio import io as audio_io
+from bumble.vendor.zephyr.hci import HCI_Write_Tx_Power_Level_Command
 
 from auracast import auracast_config
 from auracast.utils.read_lc3_file import read_lc3_file
@@ -206,7 +207,7 @@ class PyAlsaAudioInput(audio_io.ThreadedAudioInput):
             length, data = self._pcm.read_sw(frame_size + self._bang_bang)
             avail = self._pcm.avail()
             SETPOINT = 120 
-            TOLERANCE = 40 
+            TOLERANCE = 80 
             if avail < SETPOINT - TOLERANCE:
                 self._bang_bang = -1 
             elif avail > SETPOINT + TOLERANCE:
@@ -462,21 +463,6 @@ async def init_broadcast(
             ],
         )
         logger.info('Setup Advertising')
-        advertising_manufacturer_data = (
-        b''
-        if global_config.manufacturer_data == (None, None)
-        else bytes(
-            core.AdvertisingData(
-                [
-                    (
-                        core.AdvertisingData.MANUFACTURER_SPECIFIC_DATA,
-                        struct.pack('<H', global_config.manufacturer_data[0])
-                        + global_config.manufacturer_data[1],
-                    )
-                ]
-            )
-        )
-    )
         bigs[f'big{i}']['broadcast_audio_announcement'] = bap.BroadcastAudioAnnouncement(conf.id)
 
         # Build advertising data types list
@@ -519,23 +505,84 @@ async def init_broadcast(
                 advertising_sid=i,
                 primary_advertising_phy=hci.Phy.LE_1M, # 2m phy config throws error - because for primary advertising channels, 1mbit is only supported
                 secondary_advertising_phy=hci.Phy.LE_1M, # this is the secondary advertising beeing send on non advertising channels (extendend advertising)
-                #advertising_tx_power= # tx power in dbm (max 20)
+                # Pass NO_PREFERENCE (0x7F) here for two reasons:
+                # 1. The Nordic SoftDevice Controller ignores this field for
+                #    advertising sets and always returns the compile-time
+                #    CONFIG_BT_CTLR_TX_PWR_* value. The real TX power is
+                #    applied via the Zephyr VS Write_Tx_Power_Level command
+                #    issued right after create_advertising_set() returns.
+                # 2. Bumble's HCI metadata declares this field as 1-byte
+                #    *unsigned* (a bumble bug — the BT spec defines it as
+                #    signed int8), so negative values would raise
+                #    "bytes must be in range(0, 256)" at serialization.
+                advertising_tx_power=hci.HCI_LE_Set_Extended_Advertising_Parameters_Command.TX_POWER_NO_PREFERENCE,
                 #secondary_advertising_max_skip=10,
             ),
             advertising_data=(
                 bigs[f'big{i}']['broadcast_audio_announcement'].get_advertising_data()
                 + bytes(core.AdvertisingData(advertising_data_types))
-                + advertising_manufacturer_data
             ),
             periodic_advertising_parameters=bumble.device.PeriodicAdvertisingParameters(
-                periodic_advertising_interval_min=80,
-                periodic_advertising_interval_max=160,
+                # 113 * 1.25 ms = 141.25 ms. Deliberately NON-commensurate with the
+                # 10 ms ISO interval (14.125x, a 1/8-ISO fractional step) so the PA
+                # anchor walks through the ISO cycle instead of standing on it. A
+                # commensurate value (e.g. 80 = 100 ms = 10x) freezes the PA/BIG phase
+                # once the broadcaster clock is stable (LFXO), so every PA event
+                # collides with a BIG subevent and gets dropped in favour of the
+                # audio -> receivers that keep the PA synced during streaming starve
+                # it out and hit the 10 s supervision timeout (PA drop). The walk keeps
+                # the PA landing in free slots so the sync holds. Verified with an HCI
+                # sniffer: commensurate -> PA 0/s, lost @10 s; 141.25 ms -> ~2/s, holds.
+                periodic_advertising_interval_min=113,
+                periodic_advertising_interval_max=113,
             ),
             periodic_advertising_data=bigs[f'big{i}']['basic_audio_announcement'].get_advertising_data(),
             auto_restart=True,
             auto_start=True,
         )
         bigs[f'big{i}']['advertising_set'] = advertising_set
+        # NOTE: selected_tx_power below reflects the SDC's compile-time max
+        # (LE_Set_Ext_Adv_Params was sent with NO_PREFERENCE). The actual
+        # transmit power is set by the VS Write_Tx_Power_Level call below.
+        logging.debug(
+            'LE_Set_Ext_Adv_Params reports controller fallback TX power: %+d dBm (handle=%d)',
+            getattr(advertising_set, 'selected_tx_power', 0),
+            i,
+        )
+
+        # The Nordic SoftDevice Controller does not honor the per-set
+        # advertising_tx_power passed in HCI_LE_Set_Extended_Advertising_Parameters
+        # (it returns the compile-time CONFIG_BT_CTLR_TX_PWR_* value regardless).
+        # Apply the requested level via the Zephyr Vendor-Specific HCI command
+        # Write_Tx_Power_Level (opcode 0xFC0E), which the SDC honors per
+        # advertising handle. The SDC clamps the value to the nearest supported
+        # hardware step (max bounded by CONFIG_BT_CTLR_TX_PWR_PLUS_8).
+        try:
+            adv_handle = getattr(advertising_set, 'advertising_handle', i)
+            response = await device.send_command(
+                HCI_Write_Tx_Power_Level_Command(
+                    handle_type=HCI_Write_Tx_Power_Level_Command.TX_POWER_HANDLE_TYPE_ADV,
+                    connection_handle=adv_handle,
+                    tx_power_level=global_config.advertising_tx_power,
+                )
+            )
+            rp = getattr(response, 'return_parameters', None)
+            status = getattr(rp, 'status', 0xFF) if rp is not None else 0xFF
+            selected = getattr(rp, 'selected_tx_power_level', None) if rp is not None else None
+            if status == 0 and selected is not None:
+                logging.info(
+                    'Advertising TX power (VS Write_Tx_Power_Level): requested=%+d dBm, controller selected=%+d dBm (handle=%d)',
+                    global_config.advertising_tx_power,
+                    selected,
+                    adv_handle,
+                )
+            else:
+                logging.warning(
+                    'VS Write_Tx_Power_Level failed: status=0x%02X handle=%d requested=%+d dBm',
+                    status, adv_handle, global_config.advertising_tx_power,
+                )
+        except Exception as e:
+            logging.warning('VS Write_Tx_Power_Level not supported by controller: %s', e)
 
         logging.info('Start Periodic Advertising')
         await advertising_set.start_periodic()
@@ -602,6 +649,29 @@ async def init_broadcast(
     return bigs
 
 
+def _lc3_file_byte_gen(filename: str, loop: bool = False):
+    """Stream LC3 frames from disk as individual bytes, with optional looping.
+
+    Yields one byte (int) at a time so it is compatible with the existing
+    ``bytes(itertools.islice(gen, bytes_per_frame))`` consumer without loading
+    the whole file into memory.
+    """
+    while True:
+        with open(filename, 'rb') as f:
+            f.read(18)  # skip 18-byte LC3 header
+            while True:
+                size_b = f.read(2)
+                if len(size_b) < 2:
+                    break
+                frame_size = struct.unpack('=H', size_b)[0]
+                frame = f.read(frame_size)
+                if len(frame) < frame_size:
+                    break
+                yield from frame
+        if not loop:
+            return
+
+
 class Streamer():
     """
     Streamer class that supports multiple input formats. See bumble for streaming from wav or device
@@ -757,13 +827,7 @@ class Streamer():
                 big['precoded'] = True
                 big['lc3_bytes_per_frame'] = global_config.octets_per_frame
                 filename = big_config[i].audio_source.replace('file:', '')
-
-                lc3_bytes = read_lc3_file(filename)
-                lc3_frames = iter(lc3_bytes)
-
-                if big_config[i].loop:
-                    lc3_frames = itertools.cycle(lc3_frames)
-                big['lc3_frames'] = lc3_frames
+                big['lc3_frames'] = _lc3_file_byte_gen(filename, loop=big_config[i].loop)
 
             # use wav files and code them entirely before streaming
             elif big_config[i].precode_wav and big_config[i].audio_source.endswith('.wav'):
@@ -811,7 +875,11 @@ class Streamer():
                     if input_format == 'auto':
                         raise ValueError('input format details required for alsa input')
                     pcm = audio_io.PcmFormat.from_str(input_format)
-                    audio_input = AlsaArecordAudioInput(audio_source[5:], pcm)
+                    device_name = audio_source[5:]
+                    if device_name.startswith('dante_'):
+                        audio_input = PyAlsaAudioInput(device_name, pcm)
+                    else:
+                        audio_input = AlsaArecordAudioInput(device_name, pcm)
                 else:
                     audio_input = await audio_io.create_audio_input(audio_source, input_format)
                 # Store early so stop_streaming can close even if open() fails
@@ -880,6 +948,9 @@ class Streamer():
                     if lc3_frame == b'':  # Not all streams may stop at the same time
                         stream_finished[i] = True
                         continue
+
+                    for q_idx in range(big.get('num_bis', 1)):
+                        await big['iso_queues'][q_idx].write(lc3_frame)
                 else:  # code lc3 on the fly with perf counters
                     # Ensure frames generator exists (so we can aclose() on stop)
                     frames_gen = big.get('frames_gen')

src/auracast/server/multicast_frontend.py

@@ -71,6 +71,10 @@ if not is_pw_disabled():
         with st.form("signin_form"):
             pw = st.text_input("Password", type="password")
             submitted = st.form_submit_button("Sign in")
+        st.components.v1.html(
+            "<script>setTimeout(()=>window.parent.document.querySelector('input[type=\"password\"]')?.focus(),100)</script>",
+            height=0
+        )
         if submitted:
             if verify_password(pw, pw_rec):
                 st.session_state['frontend_authenticated'] = True
@@ -96,6 +100,36 @@ QOS_PRESET_MAP = {
     "Robust": auracast_config.AuracastQosRobust(),
 }
 
+# Discrete advertising TX power steps in dBm supported by the Nordic SDC radio
+# PA. Sent through HCI_LE_Set_Extended_Advertising_Parameters; the controller
+# clamps to the nearest hardware step.
+TX_POWER_OPTIONS = [8, 7, 6, 5, 4, 3, 2, 0, -4, -8, -12, -16, -20]
+TX_POWER_DEFAULT = 8
+
+
+def _coerce_tx_power(value, default: int = TX_POWER_DEFAULT) -> int:
+    try:
+        v = int(value)
+    except (TypeError, ValueError):
+        return default
+    if v in TX_POWER_OPTIONS:
+        return v
+    return min(TX_POWER_OPTIONS, key=lambda s: abs(s - v))
+
+
+def _tx_power_selectbox(label: str, key: str, default: int, disabled: bool, help_text: str | None = None) -> int:
+    snapped = _coerce_tx_power(default)
+    idx = TX_POWER_OPTIONS.index(snapped)
+    return st.selectbox(
+        label,
+        TX_POWER_OPTIONS,
+        index=idx,
+        key=key,
+        format_func=lambda v: f"{v:+d} dBm",
+        disabled=disabled,
+        help=help_text or "Bluetooth advertising TX power for this radio. Higher values increase range; lower values reduce interference and power draw.",
+    )
+
 # Try loading persisted settings from backend
 saved_settings = {}
 try:
@@ -351,6 +385,17 @@ if audio_mode == "Demo":
         disabled=is_streaming,
         help="Select the demo stream configuration."
     )
+    demo_content_options = ["Program material", "1 kHz test tone"]
+    saved_demo_content = saved_settings.get('demo_content', 'Program material')
+    if saved_demo_content not in demo_content_options:
+        saved_demo_content = 'Program material'
+    demo_content = st.selectbox(
+        "Demo Content",
+        demo_content_options,
+        index=demo_content_options.index(saved_demo_content),
+        disabled=is_streaming,
+        help="Select whether demo streams use program audio files or a continuous 1 kHz test tone."
+    )
     # Stream password and flags (same as USB/AES67)
     saved_pwd = saved_settings.get('stream_password', '') or ''
     stream_passwort = st.text_input(
@@ -394,6 +439,22 @@ if audio_mode == "Demo":
             disabled=is_streaming,
             help="Fast: 2 retransmissions, lower latency. Robust: 4 retransmissions, better reliability."
         )
+    # Per-radio TX power for Demo (independent for R1 and R2)
+    col_tx_r1, col_tx_r2 = st.columns(2, gap="small")
+    with col_tx_r1:
+        tx_power_r1 = _tx_power_selectbox(
+            "TX Power (R1)",
+            key="demo_tx_power_r1",
+            default=saved_settings.get('advertising_tx_power', TX_POWER_DEFAULT),
+            disabled=is_streaming,
+        )
+    with col_tx_r2:
+        tx_power_r2 = _tx_power_selectbox(
+            "TX Power (R2)",
+            key="demo_tx_power_r2",
+            default=saved_settings.get('secondary', {}).get('advertising_tx_power', TX_POWER_DEFAULT),
+            disabled=is_streaming,
+        )
     #st.info(f"Demo mode selected: {demo_selected} (Streams: {demo_stream_map[demo_selected]['streams']}, Rate: {demo_stream_map[demo_selected]['rate']} Hz)")
     quality = None  # Not used in demo mode
 else:
@@ -425,21 +486,52 @@ else:
                 help="Radio 1 is always enabled, Radio 2 can be turned on or off."
             )
 
-            # Stereo mode toggle for analog
-            stereo_enabled = st.checkbox(
-                "🎧 Stereo Mode",
-                value=bool(saved_settings.get('analog_stereo_mode', False)),
-                help="Enable stereo streaming for analog inputs. When enabled, ch1 becomes left channel and ch2 becomes right channel in a single stereo stream. Radio 2 will be disabled in stereo mode.",
-                disabled=is_streaming
-            )
-
-            # Use analog-specific defaults (not from saved settings which may have Dante values)
-            default_name = "Analog_Radio_1"
-            default_program_info = "Analog Radio Broadcast"
-            default_lang = "deu"
+            # Stereo mode toggle for analog (temporarily hidden from the UI)
+            stereo_enabled = False
+            # stereo_enabled = st.checkbox(
+            #     "🎧 Stereo Mode",
+            #     value=bool(saved_settings.get('analog_stereo_mode', False)),
+            #     help="Enable stereo streaming for analog inputs. When enabled, ch1 becomes left channel and ch2 becomes right channel in a single stereo stream. Radio 2 will be disabled in stereo mode.",
+            #     disabled=is_streaming
+            # )
 
             quality_options = list(QUALITY_MAP.keys())
-            default_quality = "Medium (24kHz)" if "Medium (24kHz)" in quality_options else quality_options[0]
+
+            # Use saved settings if audio_mode matches, otherwise use analog-specific defaults
+            saved_audio_mode = saved_settings.get('audio_mode')
+            if saved_audio_mode == 'Analog':
+                default_name = saved_settings.get('channel_names', ["Analog_Radio_1"])[0]
+                raw_program_info = saved_settings.get('program_info', default_name)
+                if isinstance(raw_program_info, list) and raw_program_info:
+                    default_program_info = raw_program_info[0]
+                else:
+                    default_program_info = raw_program_info
+                default_lang = saved_settings.get('languages', ["deu"])[0]
+
+                # Map saved sampling rate to quality label
+                saved_rate = saved_settings.get('auracast_sampling_rate_hz')
+                if saved_rate == 48000:
+                    default_quality = "High (48kHz)"
+                elif saved_rate == 32000:
+                    default_quality = "Good (32kHz)"
+                elif saved_rate == 24000:
+                    default_quality = "Medium (24kHz)"
+                elif saved_rate == 16000:
+                    default_quality = "Fair (16kHz)"
+                else:
+                    default_quality = "Medium (24kHz)"
+
+                saved_pwd = saved_settings.get('stream_password', '')
+            else:
+                # Use analog-specific defaults when switching from another mode
+                default_name = "Analog_Radio_1"
+                default_program_info = "Analog Radio Broadcast"
+                default_lang = "deu"
+                default_quality = "Medium (24kHz)" if "Medium (24kHz)" in quality_options else quality_options[0]
+                saved_pwd = ''
+
+            if default_quality not in quality_options:
+                default_quality = quality_options[0]
             quality1 = st.selectbox(
                 "Stream Quality (Radio 1)",
                 quality_options,
@@ -450,7 +542,7 @@ else:
 
             stream_passwort1 = st.text_input(
                 "Stream Passwort (Radio 1)",
-                value="",
+                value=saved_pwd,
                 type="password",
                 disabled=is_streaming,
                 help="Optional: Set a broadcast code for Radio 1."
@@ -490,6 +582,13 @@ else:
                     help="Fast: 2 retransmissions, lower latency. Robust: 4 retransmissions, better reliability."
                 )
 
+            tx_power_r1 = _tx_power_selectbox(
+                "TX Power (R1)",
+                key="analog_tx_power_r1",
+                default=saved_settings.get('advertising_tx_power', TX_POWER_DEFAULT),
+                disabled=is_streaming,
+            )
+
             col_r1_name, col_r1_lang = st.columns([2, 1])
             with col_r1_name:
                 stream_name1 = st.text_input(
@@ -557,7 +656,10 @@ else:
                             input_device1 = None
                     else:
                         # Mono mode: show all available channels
+                        saved_input_device = saved_settings.get('input_device')
                         default_r1_idx = 0
+                        if saved_input_device in analog_names:
+                            default_r1_idx = analog_names.index(saved_input_device)
                         input_device1 = st.selectbox(
                             "Input Device (Radio 1)",
                             analog_names,
@@ -606,22 +708,53 @@ else:
                 )
 
             if radio2_enabled and not stereo_enabled:
-                # Use analog-specific defaults for Radio 2
-                default_name_r2 = "Analog_Radio_2"
-                default_program_info_r2 = "Analog Radio Broadcast"
-                default_lang_r2 = "deu"
+                # Use saved settings if audio_mode matches, otherwise use analog-specific defaults for Radio 2
+                secondary_settings = saved_settings.get('secondary', {})
+                saved_audio_mode = saved_settings.get('audio_mode')
+                if saved_audio_mode == 'Analog' and secondary_settings:
+                    default_name_r2 = secondary_settings.get('channel_names', ["Analog_Radio_2"])[0] if isinstance(secondary_settings.get('channel_names'), list) else secondary_settings.get('channel_names', "Analog_Radio_2")
+                    raw_program_info_r2 = secondary_settings.get('program_info', default_name_r2)
+                    if isinstance(raw_program_info_r2, list) and raw_program_info_r2:
+                        default_program_info_r2 = raw_program_info_r2[0]
+                    else:
+                        default_program_info_r2 = raw_program_info_r2
+                    default_lang_r2 = secondary_settings.get('languages', ["deu"])[0] if isinstance(secondary_settings.get('languages'), list) else secondary_settings.get('languages', 'deu')
                     
+                    # Map saved sampling rate to quality label
+                    saved_rate_r2 = secondary_settings.get('auracast_sampling_rate_hz')
+                    if saved_rate_r2 == 48000:
+                        default_quality_r2 = "High (48kHz)"
+                    elif saved_rate_r2 == 32000:
+                        default_quality_r2 = "Good (32kHz)"
+                    elif saved_rate_r2 == 24000:
+                        default_quality_r2 = "Medium (24kHz)"
+                    elif saved_rate_r2 == 16000:
+                        default_quality_r2 = "Fair (16kHz)"
+                    else:
+                        default_quality_r2 = "Medium (24kHz)"
+                    
+                    saved_pwd_r2 = secondary_settings.get('stream_password', '')
+                else:
+                    # Use analog-specific defaults when switching from another mode
+                    default_name_r2 = "Analog_Radio_2"
+                    default_program_info_r2 = "Analog Radio Broadcast"
+                    default_lang_r2 = "deu"
+                    default_quality_r2 = "Medium (24kHz)" if "Medium (24kHz)" in quality_options else quality_options[0]
+                    saved_pwd_r2 = ''
+
+                if default_quality_r2 not in quality_options:
+                    default_quality_r2 = quality_options[0]
                 quality2 = st.selectbox(
                     "Stream Quality (Radio 2)",
                     quality_options,
-                    index=quality_options.index(default_quality),
+                    index=quality_options.index(default_quality_r2),
                     disabled=is_streaming,
                     help="Select the audio sampling rate for Radio 2."
                 )
 
                 stream_passwort2 = st.text_input(
                     "Stream Passwort (Radio 2)",
-                    value="",
+                    value=saved_pwd_r2,
                     type="password",
                     disabled=is_streaming,
                     help="Optional: Set a broadcast code for Radio 2."
@@ -658,6 +791,13 @@ else:
                         help="Fast: 2 retransmissions, lower latency. Robust: 4 retransmissions, better reliability."
                     )
 
+                tx_power_r2 = _tx_power_selectbox(
+                    "TX Power (R2)",
+                    key="analog_tx_power_r2",
+                    default=saved_settings.get('secondary', {}).get('advertising_tx_power', TX_POWER_DEFAULT),
+                    disabled=is_streaming,
+                )
+
                 col_r2_name, col_r2_lang = st.columns([2, 1])
                 with col_r2_name:
                     stream_name2 = st.text_input(
@@ -682,7 +822,11 @@ else:
 
                 if not is_streaming:
                     if analog_names:
+                        secondary_settings = saved_settings.get('secondary', {})
+                        saved_input_device2 = secondary_settings.get('input_device')
                         default_r2_idx = 1 if len(analog_names) > 1 else 0
+                        if saved_input_device2 in analog_names:
+                            default_r2_idx = analog_names.index(saved_input_device2)
                         input_device2 = st.selectbox(
                             "Input Device (Radio 2)",
                             analog_names,
@@ -692,7 +836,7 @@ else:
                     else:
                         input_device2 = None
                 else:
-                    input_device2 = saved_settings.get('input_device')
+                    input_device2 = saved_settings.get('secondary', {}).get('input_device')
                     st.selectbox(
                         "Input Device (Radio 2)",
                         [input_device2 or "No device selected"],
@@ -713,6 +857,7 @@ else:
                     'immediate_rendering': immediate_rendering2,
                     'presentation_delay_ms': presentation_delay_ms2,
                     'qos_preset': qos_preset2,
+                    'tx_power': tx_power_r2,
                     'analog_gain_db_left': analog_gain_db_left,
                     'analog_gain_db_right': analog_gain_db_right,
                 }
@@ -729,6 +874,7 @@ else:
             'immediate_rendering': immediate_rendering1,
             'presentation_delay_ms': presentation_delay_ms1,
             'qos_preset': qos_preset1,
+            'tx_power': tx_power_r1,
             'stereo_mode': stereo_enabled,
             'analog_gain_db_left': analog_gain_db_left,
             'analog_gain_db_right': analog_gain_db_right,
@@ -773,14 +919,19 @@ else:
                 help="Radio 1 is always enabled, Radio 2 can be turned on or off."
             )
             
-            # Dante stereo mode toggle
-            saved_r1_config = saved_settings.get('dante_radio1', {})
-            dante_stereo_enabled = st.checkbox(
-                "🎧 Stereo Mode",
-                value=bool(saved_r1_config.get('dante_stereo_mode', False)),
-                help="Enable stereo streaming for Dante inputs. Select left and right channels from ASRC channels 1-6. Radio 2 and multi-stream configurations will be disabled in stereo mode.",
-                disabled=is_streaming
-            )
+            # Dante stereo mode toggle (temporarily hidden from the UI)
+            saved_audio_mode = saved_settings.get('audio_mode')
+            dante_stereo_enabled = False
+            # if saved_audio_mode == 'Network - Dante':
+            #     # Check if any input device starts with dante_stereo_ to detect stereo mode
+            #     input_device = saved_settings.get('input_device', '')
+            #     dante_stereo_enabled = input_device.startswith('dante_stereo_')
+            # dante_stereo_enabled = st.checkbox(
+            #     "🎧 Stereo Mode",
+            #     value=dante_stereo_enabled,
+            #     help="Enable stereo streaming for Dante inputs. Select left and right channels from ASRC channels 1-6. Radio 2 and multi-stream configurations will be disabled in stereo mode.",
+            #     disabled=is_streaming
+            # )
             
             # Dante stereo channel selectors
             dante_left_channel = None
@@ -790,9 +941,19 @@ else:
                                          "dante_asrc_ch4", "dante_asrc_ch5", "dante_asrc_ch6"]
                 dante_channel_labels = ["CH1", "CH2", "CH3", "CH4", "CH5", "CH6"]
 
+                # Parse saved stereo device name to extract left and right channels
+                input_device = saved_settings.get('input_device', '')
+                saved_left = 'dante_asrc_ch1'
+                saved_right = 'dante_asrc_ch2'
+                if input_device.startswith('dante_stereo_'):
+                    # Format: dante_stereo_<left>_<right>
+                    parts = input_device.split('_')
+                    if len(parts) >= 4:
+                        saved_left = f"dante_asrc_ch{parts[2]}"
+                        saved_right = f"dante_asrc_ch{parts[3]}"
+
                 col_left, col_right = st.columns(2)
                 with col_left:
-                    saved_left = saved_r1_config.get('dante_stereo_left', 'dante_asrc_ch1')
                     left_idx = dante_channel_options.index(saved_left) if saved_left in dante_channel_options else 0
                     dante_left_channel = st.selectbox(
                         "Left Channel",
@@ -803,7 +964,6 @@ else:
                         help="Select the Dante ASRC channel for the left stereo channel"
                     )
                 with col_right:
-                    saved_right = saved_r1_config.get('dante_stereo_right', 'dante_asrc_ch2')
                     right_idx = dante_channel_options.index(saved_right) if saved_right in dante_channel_options else 1
                     dante_right_channel = st.selectbox(
                         "Right Channel",
@@ -821,7 +981,22 @@ else:
             
             # Stream count dropdown for Radio 1 (disabled in stereo mode - forced to 1 stream at 48kHz)
             r1_stream_options = list(dante_stream_options.keys())
-            saved_r1_streams = saved_r1_config.get('stream_config', '1x48')
+            # Infer stream configuration from saved sampling rate
+            saved_rate = saved_settings.get('auracast_sampling_rate_hz')
+            saved_r1_streams = '1 × 48kHz'  # default
+            if saved_rate:
+                if saved_rate == 48000:
+                    channel_names = saved_settings.get('channel_names', [])
+                    if len(channel_names) == 2:
+                        saved_r1_streams = '2 × 24kHz'
+                    elif len(channel_names) == 3:
+                        saved_r1_streams = '3 × 16kHz'
+                    else:
+                        saved_r1_streams = '1 × 48kHz'
+                elif saved_rate == 24000:
+                    saved_r1_streams = '2 × 24kHz'
+                elif saved_rate == 16000:
+                    saved_r1_streams = '3 × 16kHz'
             default_r1_idx = r1_stream_options.index(saved_r1_streams) if saved_r1_streams in r1_stream_options else 0
             
             if dante_stereo_enabled:
@@ -856,7 +1031,17 @@ else:
                     (r1_max_quality == "Fair (16kHz)" and quality == "Fair (16kHz)")):
                     r1_available_qualities.append(quality)
 
-            saved_r1_quality = saved_r1_config.get('radio_quality', r1_max_quality)
+            # Map saved sampling rate to quality label
+            saved_r1_quality = r1_max_quality
+            saved_rate = saved_settings.get('auracast_sampling_rate_hz')
+            if saved_rate == 48000:
+                saved_r1_quality = "High (48kHz)"
+            elif saved_rate == 32000:
+                saved_r1_quality = "Good (32kHz)"
+            elif saved_rate == 24000:
+                saved_r1_quality = "Medium (24kHz)"
+            elif saved_rate == 16000:
+                saved_r1_quality = "Fair (16kHz)"
             if saved_r1_quality not in r1_available_qualities:
                 saved_r1_quality = r1_max_quality
 
@@ -875,7 +1060,7 @@ else:
             with col_r1_flags1:
                 r1_assisted_listening = st.checkbox(
                     "Assistive (R1)",
-                    value=bool(saved_r1_config.get('assisted_listening', False)),
+                    value=bool(saved_settings.get('assisted_listening_stream', False)),
                     disabled=is_streaming,
                     help="Assistive listening stream"
                 )
@@ -883,13 +1068,13 @@ else:
             with col_r1_flags2:
                 r1_immediate_rendering = st.checkbox(
                     "Immediate (R1)",
-                    value=bool(saved_r1_config.get('immediate_rendering', False)),
+                    value=bool(saved_settings.get('immediate_rendering', False)),
                     disabled=is_streaming,
                     help="Ignore presentation delay"
                 )
             
             with col_r1_pdelay:
-                default_pdelay = int(saved_r1_config.get('presentation_delay_us', 40000) or 40000)
+                default_pdelay = int(saved_settings.get('presentation_delay_us', 40000) or 40000)
                 default_pdelay_ms = max(10, min(200, default_pdelay // 1000))
                 r1_presentation_delay_ms = st.number_input(
                     "Delay (ms, R1)",
@@ -900,7 +1085,7 @@ else:
 
             with col_r1_qos:
                 qos_options = list(QOS_PRESET_MAP.keys())
-                saved_qos = saved_r1_config.get('qos_preset', 'Fast')
+                saved_qos = saved_settings.get('qos_preset', 'Fast')
                 default_qos_idx = qos_options.index(saved_qos) if saved_qos in qos_options else 0
                 r1_qos_preset = st.selectbox(
                     "QoS (R1)", options=qos_options, index=default_qos_idx,
@@ -908,6 +1093,13 @@ else:
                     help="Quality of Service preset for Radio 1"
                 )
 
+            r1_tx_power = _tx_power_selectbox(
+                "TX Power (R1)",
+                key="dante_tx_power_r1",
+                default=saved_settings.get('advertising_tx_power', TX_POWER_DEFAULT),
+                disabled=is_streaming,
+            )
+
             # Per-stream configuration for Radio 1
             if dante_stereo_enabled:
                 st.write("**Stereo Stream Configuration (Radio 1)**")
@@ -918,8 +1110,15 @@ else:
             if dante_stereo_enabled:
                 # Stereo mode: single stream with combined L+R channels
                 with st.expander("Stereo Stream - Radio 1", expanded=True):
-                    saved_streams = saved_r1_config.get('streams', [])
-                    saved_stream = saved_streams[0] if saved_streams else {}
+                    # Read from flat settings structure
+                    channel_names = saved_settings.get('channel_names', [])
+                    program_infos = saved_settings.get('program_info', [])
+                    languages = saved_settings.get('languages', [])
+
+                    saved_name = channel_names[0] if channel_names else 'Dante_Stereo'
+                    saved_program_info = program_infos[0] if program_infos else saved_name
+                    saved_language = languages[0] if languages else 'eng'
+                    saved_password = saved_settings.get('stream_password', '')
 
                     # First row: Channel name and password
                     col_name, col_pwd = st.columns([2, 1])
@@ -927,7 +1126,7 @@ else:
                     with col_name:
                         stream_name = st.text_input(
                             "Channel Name",
-                            value=saved_stream.get('name', 'Dante_Stereo'),
+                            value=saved_name,
                             disabled=is_streaming,
                             key="r1_stereo_name"
                         )
@@ -935,7 +1134,7 @@ else:
                     with col_pwd:
                         stream_password = st.text_input(
                             "Stream Password",
-                            value=saved_stream.get('stream_password', ''),
+                            value=saved_password,
                             type="password",
                             disabled=is_streaming,
                             key="r1_stereo_password",
@@ -948,7 +1147,7 @@ else:
                     with col_prog:
                         program_info = st.text_input(
                             "Program Info",
-                            value=saved_stream.get('program_info', 'Dante Stereo Broadcast'),
+                            value=saved_program_info,
                             disabled=is_streaming,
                             key="r1_stereo_program"
                         )
@@ -956,7 +1155,7 @@ else:
                     with col_lang_code:
                         language = st.text_input(
                             "Language",
-                            value=saved_stream.get('language', 'eng'),
+                            value=saved_language,
                             disabled=is_streaming,
                             key="r1_stereo_lang",
                             help="ISO 639-3 language code"
@@ -990,10 +1189,21 @@ else:
                     })
             else:
                 # Normal mono mode: multiple streams with individual channels
+                # Read from flat settings structure
+                channel_names = saved_settings.get('channel_names', [])
+                program_infos = saved_settings.get('program_info', [])
+                languages = saved_settings.get('languages', [])
+                input_devices = saved_settings.get('input_devices', [])
+                stream_passwords = saved_settings.get('stream_passwords', []) if 'stream_passwords' in saved_settings else []
+
                 for i in range(r1_num_streams):
                     with st.expander(f"Stream {i+1} - Radio 1", expanded=True):
-                        saved_streams = saved_r1_config.get('streams', [])
-                        saved_stream = saved_streams[i] if i < len(saved_streams) else {}
+                        # Get saved values from flat structure
+                        saved_name = channel_names[i] if i < len(channel_names) else f'Dante_R1_S{i+1}'
+                        saved_program_info = program_infos[i] if i < len(program_infos) else f'Dante Radio 1 Stream {i+1}'
+                        saved_language = languages[i] if i < len(languages) else 'eng'
+                        saved_password = stream_passwords[i] if i < len(stream_passwords) else ''
+                        saved_input_device = input_devices[i] if i < len(input_devices) else None
 
                         # First row: Channel name and language
                         col_name, col_lang = st.columns([2, 1])
@@ -1001,7 +1211,7 @@ else:
                         with col_name:
                             stream_name = st.text_input(
                                 f"Channel Name",
-                                value=saved_stream.get('name', f'Dante_R1_S{i+1}'),
+                                value=saved_name,
                                 disabled=is_streaming,
                                 key=f"r1_stream_{i}_name"
                             )
@@ -1009,7 +1219,7 @@ else:
                         with col_lang:
                             stream_password = st.text_input(
                                 f"Stream Password",
-                                value=saved_stream.get('stream_password', ''),
+                                value=saved_password,
                                 type="password",
                                 disabled=is_streaming,
                                 key=f"r1_stream_{i}_password",
@@ -1022,7 +1232,7 @@ else:
                         with col_prog:
                             program_info = st.text_input(
                                 f"Program Info",
-                                value=saved_stream.get('program_info', f'Dante Radio 1 Stream {i+1}'),
+                                value=saved_program_info,
                                 disabled=is_streaming,
                                 key=f"r1_stream_{i}_program"
                             )
@@ -1030,7 +1240,7 @@ else:
                         with col_lang_code:
                             language = st.text_input(
                                 f"Language",
-                                value=saved_stream.get('language', 'eng'),
+                                value=saved_language,
                                 disabled=is_streaming,
                                 key=f"r1_stream_{i}_lang",
                                 help="ISO 639-3 language code"
@@ -1045,7 +1255,7 @@ else:
 
                             if not is_streaming and input_options:
                                 # Get default from session state first, then from saved settings
-                                default_input_name = st.session_state.get(device_session_key, saved_stream.get('input_device'))
+                                default_input_name = st.session_state.get(device_session_key, saved_input_device)
                                 default_input_label = None
                                 for label, name in option_name_map.items():
                                     if name == default_input_name:
@@ -1066,7 +1276,7 @@ else:
                                 st.session_state[device_session_key] = input_device
                             else:
                                 # When streaming, get the device from session state
-                                current_device = st.session_state.get(device_session_key, saved_stream.get('input_device', 'No device'))
+                                current_device = st.session_state.get(device_session_key, saved_input_device or 'No device')
                                 
                                 # Convert internal name to display label
                                 display_label = current_device
@@ -1097,13 +1307,17 @@ else:
             st.subheader("Radio 2")
 
             # Disable Radio 2 in stereo mode
-            saved_r2_config = saved_settings.get('dante_radio2', {})
+            secondary_settings = saved_settings.get('secondary', {})
             if dante_stereo_enabled:
                 st.info("🎧 Radio 2 is automatically disabled in stereo mode")
                 radio2_enabled = False
             else:
                 # Enable/disable checkbox for Radio 2
+                # Use saved settings or streaming state to determine default
                 radio2_enabled_default = secondary_is_streaming
+                # Check if secondary radio has saved settings (indicates it was enabled)
+                if secondary_settings.get('auracast_sampling_rate_hz') or secondary_settings.get('channel_names'):
+                    radio2_enabled_default = True
                 radio2_enabled = st.checkbox(
                     "Enable Radio 2",
                     value=radio2_enabled_default,
@@ -1114,7 +1328,22 @@ else:
             if radio2_enabled:
                 # Stream count dropdown for Radio 2
                 r2_stream_options = r1_stream_options
-                saved_r2_streams = saved_r2_config.get('stream_config', '1x48')
+                # Infer stream configuration from saved secondary sampling rate
+                saved_rate2 = secondary_settings.get('auracast_sampling_rate_hz')
+                saved_r2_streams = '1 × 48kHz'  # default
+                if saved_rate2:
+                    if saved_rate2 == 48000:
+                        channel_names2 = secondary_settings.get('channel_names', [])
+                        if len(channel_names2) == 2:
+                            saved_r2_streams = '2 × 24kHz'
+                        elif len(channel_names2) == 3:
+                            saved_r2_streams = '3 × 16kHz'
+                        else:
+                            saved_r2_streams = '1 × 48kHz'
+                    elif saved_rate2 == 24000:
+                        saved_r2_streams = '2 × 24kHz'
+                    elif saved_rate2 == 16000:
+                        saved_r2_streams = '3 × 16kHz'
                 default_r2_idx = r2_stream_options.index(saved_r2_streams) if saved_r2_streams in r2_stream_options else 0
                 
                 r2_stream_config = st.selectbox(
@@ -1137,7 +1366,16 @@ else:
                         (r2_max_quality == "Fair (16kHz)" and quality == "Fair (16kHz)")):
                         r2_available_qualities.append(quality)
 
-                saved_r2_quality = saved_r2_config.get('radio_quality', r2_max_quality)
+                # Map saved secondary sampling rate to quality label
+                saved_r2_quality = r2_max_quality
+                if saved_rate2 == 48000:
+                    saved_r2_quality = "High (48kHz)"
+                elif saved_rate2 == 32000:
+                    saved_r2_quality = "Good (32kHz)"
+                elif saved_rate2 == 24000:
+                    saved_r2_quality = "Medium (24kHz)"
+                elif saved_rate2 == 16000:
+                    saved_r2_quality = "Fair (16kHz)"
                 if saved_r2_quality not in r2_available_qualities:
                     saved_r2_quality = r2_max_quality
 
@@ -1150,13 +1388,12 @@ else:
                 )
 
                 # Radio-level settings for Radio 2
-                # First row: Assistive listening, immediate rendering, presentation delay, QoS
                 col_r2_flags1, col_r2_flags2, col_r2_pdelay, col_r2_qos = st.columns([1, 1, 0.7, 0.6], gap="small")
 
                 with col_r2_flags1:
                     r2_assisted_listening = st.checkbox(
                         "Assistive (R2)",
-                        value=bool(saved_r2_config.get('assisted_listening', False)),
+                        value=bool(secondary_settings.get('assisted_listening_stream', False)),
                         disabled=is_streaming,
                         help="Assistive listening stream"
                     )
@@ -1164,13 +1401,13 @@ else:
                 with col_r2_flags2:
                     r2_immediate_rendering = st.checkbox(
                         "Immediate (R2)",
-                        value=bool(saved_r2_config.get('immediate_rendering', False)),
+                        value=bool(secondary_settings.get('immediate_rendering', False)),
                         disabled=is_streaming,
                         help="Ignore presentation delay"
                     )
 
                 with col_r2_pdelay:
-                    default_pdelay = int(saved_r2_config.get('presentation_delay_us', 40000) or 40000)
+                    default_pdelay = int(secondary_settings.get('presentation_delay_us', 40000) or 40000)
                     default_pdelay_ms = max(10, min(200, default_pdelay // 1000))
                     r2_presentation_delay_ms = st.number_input(
                         "Delay (ms, R2)",
@@ -1181,22 +1418,40 @@ else:
 
                 with col_r2_qos:
                     qos_options = list(QOS_PRESET_MAP.keys())
-                    saved_qos = saved_r2_config.get('qos_preset', 'Fast')
-                    default_qos_idx = qos_options.index(saved_qos) if saved_qos in qos_options else 0
+                    saved_qos = secondary_settings.get('qos_preset', 'Fast')
+                    default_qos_idx2 = qos_options.index(saved_qos) if saved_qos in qos_options else 0
                     r2_qos_preset = st.selectbox(
-                        "QoS (R2)", options=qos_options, index=default_qos_idx,
+                        "QoS (R2)", options=qos_options, index=default_qos_idx2,
                         disabled=is_streaming,
                         help="Quality of Service preset for Radio 2"
                     )
 
+                r2_tx_power = _tx_power_selectbox(
+                    "TX Power (R2)",
+                    key="dante_tx_power_r2",
+                    default=saved_settings.get('secondary', {}).get('advertising_tx_power', TX_POWER_DEFAULT),
+                    disabled=is_streaming,
+                )
+
                 # Per-stream configuration for Radio 2
                 st.write("**Stream Configuration (Radio 2)**")
                 r2_streams = []
 
+                # Read from flat secondary settings structure
+                channel_names2 = secondary_settings.get('channel_names', [])
+                program_infos2 = secondary_settings.get('program_info', [])
+                languages2 = secondary_settings.get('languages', [])
+                input_devices2 = secondary_settings.get('input_devices', [])
+                stream_passwords2 = secondary_settings.get('stream_passwords', []) if 'stream_passwords' in secondary_settings else []
+
                 for i in range(r2_num_streams):
                     with st.expander(f"Stream {i+1} - Radio 2", expanded=True):
-                        saved_streams = saved_r2_config.get('streams', [])
-                        saved_stream = saved_streams[i] if i < len(saved_streams) else {}
+                        # Get saved values from flat secondary structure
+                        saved_name2 = channel_names2[i] if i < len(channel_names2) else f'Dante_R2_S{i+1}'
+                        saved_program_info2 = program_infos2[i] if i < len(program_infos2) else f'Dante Radio 2 Stream {i+1}'
+                        saved_language2 = languages2[i] if i < len(languages2) else 'eng'
+                        saved_password2 = stream_passwords2[i] if i < len(stream_passwords2) else ''
+                        saved_input_device2 = input_devices2[i] if i < len(input_devices2) else None
 
                         # First row: Channel name and password
                         col_name, col_pwd = st.columns([2, 1])
@@ -1204,7 +1459,7 @@ else:
                         with col_name:
                             stream_name = st.text_input(
                                 f"Channel Name",
-                                value=saved_stream.get('name', f'Dante_R2_S{i+1}'),
+                                value=saved_name2,
                                 disabled=is_streaming,
                                 key=f"r2_stream_{i}_name"
                             )
@@ -1212,7 +1467,7 @@ else:
                         with col_pwd:
                             stream_password = st.text_input(
                                 f"Stream Password",
-                                value=saved_stream.get('stream_password', ''),
+                                value=saved_password2,
                                 type="password",
                                 disabled=is_streaming,
                                 key=f"r2_stream_{i}_password",
@@ -1225,7 +1480,7 @@ else:
                         with col_prog:
                             program_info = st.text_input(
                                 f"Program Info",
-                                value=saved_stream.get('program_info', f'Dante Radio 2 Stream {i+1}'),
+                                value=saved_program_info2,
                                 disabled=is_streaming,
                                 key=f"r2_stream_{i}_program"
                             )
@@ -1233,7 +1488,7 @@ else:
                         with col_lang:
                             language = st.text_input(
                                 f"Language",
-                                value=saved_stream.get('language', 'eng'),
+                                value=saved_language2,
                                 disabled=is_streaming,
                                 key=f"r2_stream_{i}_lang",
                                 help="ISO 639-3 language code"
@@ -1248,7 +1503,7 @@ else:
 
                             if not is_streaming and input_options:
                                 # Get default from session state first, then from saved settings
-                                default_input_name = st.session_state.get(device_session_key, saved_stream.get('input_device'))
+                                default_input_name = st.session_state.get(device_session_key, saved_input_device2)
                                 default_input_label = None
                                 for label, name in option_name_map.items():
                                     if name == default_input_name:
@@ -1269,7 +1524,7 @@ else:
                                 st.session_state[device_session_key] = input_device
                             else:
                                 # When streaming, get the device from session state
-                                current_device = st.session_state.get(device_session_key, saved_stream.get('input_device', 'No device'))
+                                current_device = st.session_state.get(device_session_key, saved_input_device2 or 'No device')
                                 
                                 # Convert internal name to display label
                                 display_label = current_device
@@ -1304,6 +1559,7 @@ else:
                 r2_immediate_rendering = False
                 r2_presentation_delay_ms = 40
                 r2_qos_preset = 'Fast'
+                r2_tx_power = TX_POWER_DEFAULT
         
         # Validate unique input devices for Network - Dante mode
         if audio_mode == "Network - Dante":
@@ -1335,6 +1591,7 @@ else:
             'immediate_rendering': r1_immediate_rendering,
             'presentation_delay_ms': r1_presentation_delay_ms,
             'qos_preset': r1_qos_preset,
+            'tx_power': r1_tx_power,
             'dante_stereo_mode': dante_stereo_enabled,
             'dante_stereo_left': dante_left_channel,
             'dante_stereo_right': dante_right_channel,
@@ -1350,12 +1607,34 @@ else:
             'immediate_rendering': r2_immediate_rendering if radio2_enabled else False,
             'presentation_delay_ms': r2_presentation_delay_ms if radio2_enabled else 40000,
             'qos_preset': r2_qos_preset if radio2_enabled else 'Fast',
+            'tx_power': r2_tx_power if radio2_enabled else TX_POWER_DEFAULT,
         } if radio2_enabled else None
         
     if audio_mode in ("USB", "Network"):
         # USB/Network: single set of controls shared with the single channel
+        # Use saved settings if audio_mode matches, otherwise use defaults
         quality_options = list(QUALITY_MAP.keys())
-        default_quality = "Medium (24kHz)" if "Medium (24kHz)" in quality_options else quality_options[0]
+        saved_audio_mode = saved_settings.get('audio_mode')
+        if saved_audio_mode in ("USB", "Network"):
+            # Map saved sampling rate to quality label
+            saved_rate = saved_settings.get('auracast_sampling_rate_hz')
+            if saved_rate == 48000:
+                default_quality = "High (48kHz)"
+            elif saved_rate == 32000:
+                default_quality = "Good (32kHz)"
+            elif saved_rate == 24000:
+                default_quality = "Medium (24kHz)"
+            elif saved_rate == 16000:
+                default_quality = "Fair (16kHz)"
+            else:
+                default_quality = "Medium (24kHz)"
+            saved_pwd = saved_settings.get('stream_password', '')
+        else:
+            # Use defaults when switching from another mode
+            default_quality = "Medium (24kHz)" if "Medium (24kHz)" in quality_options else quality_options[0]
+            saved_pwd = ''
+        if default_quality not in quality_options:
+            default_quality = quality_options[0]
         quality = st.selectbox(
             "Stream Quality (Sampling Rate)",
             quality_options,
@@ -1366,7 +1645,7 @@ else:
 
         stream_passwort = st.text_input(
             "Stream Passwort",
-            value="",
+            value=saved_pwd,
             type="password",
             disabled=is_streaming,
             help="Optional: Set a broadcast code to protect your stream. Leave empty for an open (uncoded) broadcast."
@@ -1406,6 +1685,13 @@ else:
                 help="Fast: 2 retransmissions, lower latency. Robust: 4 retransmissions, better reliability."
             )
 
+        tx_power = _tx_power_selectbox(
+            "TX Power",
+            key="usb_tx_power",
+            default=saved_settings.get('advertising_tx_power', TX_POWER_DEFAULT),
+            disabled=is_streaming,
+        )
+
         stream_name = st.text_input(
             "Channel Name",
             value=default_name,
@@ -1537,12 +1823,22 @@ if start_stream:
         bigs1 = []
         for i in range(demo_cfg['streams']):
             cfg_cls, lang = lang_cfgs[i % len(lang_cfgs)]
+            if demo_content == "1 kHz test tone":
+                source_file = f'../testdata/test_tone_1k_{int(q["rate"]/1000)}kHz_mono.lc3'
+                big_kwargs = {
+                    'name': 'test tone',
+                    'program_info': '1khz',
+                }
+            else:
+                source_file = f'../testdata/wave_particle_5min_{lang}_{int(q["rate"]/1000)}kHz_mono.lc3'
+                big_kwargs = {}
             bigs1.append(cfg_cls(
                 code=(stream_passwort.strip() or None),
-                audio_source=f'file:../testdata/wave_particle_5min_{lang}_{int(q["rate"]/1000)}kHz_mono.wav',
+                audio_source=f'file:{source_file}',
                 iso_que_len=32,
                 sampling_frequency=q['rate'],
                 octets_per_frame=q['octets'],
+                **big_kwargs,
             ))
 
         max_per_mc = {48000: 1, 24000: 2, 16000: 3}
@@ -1559,6 +1855,7 @@ if start_stream:
             immediate_rendering=immediate_rendering,
             presentation_delay_us=int(presentation_delay_ms * 1000),
             qos_config=QOS_PRESET_MAP[qos_preset],
+            advertising_tx_power=tx_power_r1,
             bigs=bigs1
         )
         config2 = None
@@ -1571,6 +1868,7 @@ if start_stream:
                 immediate_rendering=immediate_rendering,
                 presentation_delay_us=int(presentation_delay_ms * 1000),
                 qos_config=QOS_PRESET_MAP[qos_preset],
+                advertising_tx_power=tx_power_r2,
                 bigs=bigs2
             )
 
@@ -1603,7 +1901,9 @@ if start_stream:
             q = QUALITY_MAP[cfg['quality']]
             
             # Determine if this is stereo mode (only applicable for analog)
-            stereo_mode = cfg.get('stereo_mode', False)
+            # Stereo is temporarily disabled in the UI; force mono regardless of any
+            # lingering saved 'stereo_mode' flag.
+            stereo_mode = False  # cfg.get('stereo_mode', False)
             channels = 2 if stereo_mode else 1
             
             return auracast_config.AuracastConfigGroup(
@@ -1614,11 +1914,12 @@ if start_stream:
                 immediate_rendering=bool(cfg['immediate_rendering']),
                 presentation_delay_us=int(cfg['presentation_delay_ms'] * 1000),
                 qos_config=QOS_PRESET_MAP[cfg['qos_preset']],
+                advertising_tx_power=int(cfg.get('tx_power', TX_POWER_DEFAULT)),
                 analog_gain_db_left=cfg.get('analog_gain_db_left', 0.0),
                 analog_gain_db_right=cfg.get('analog_gain_db_right', 0.0),
                 bigs=[
                     auracast_config.AuracastBigConfig(
-                        code=(cfg['stream_passwort'].strip() or None),
+                        code=((cfg['stream_passwort'] or '').strip() or None),
                         name=cfg['name'],
                         program_info=cfg['program_info'],
                         language=cfg['language'],
@@ -1665,7 +1966,9 @@ if start_stream:
             bigs = []
             
             # Check if stereo mode is enabled for this radio
-            is_stereo_mode = bool(radio_cfg.get('dante_stereo_mode', False))
+            # Stereo is temporarily disabled in the UI; force mono regardless of any
+            # lingering saved 'dante_stereo_mode' flag or 'dante_stereo_' input device.
+            is_stereo_mode = False  # bool(radio_cfg.get('dante_stereo_mode', False))
 
             for i, stream in enumerate(radio_cfg['streams']):
                 if not stream.get('input_device'):
@@ -1673,7 +1976,7 @@ if start_stream:
 
                 # Check if this specific stream uses stereo (dante_stereo_X_Y device)
                 input_device = stream['input_device']
-                stream_is_stereo = is_stereo_mode or input_device.startswith('dante_stereo_')
+                stream_is_stereo = False  # is_stereo_mode or input_device.startswith('dante_stereo_')
                 num_bis = 2 if stream_is_stereo else 1
                 num_channels = 2 if stream_is_stereo else 1
                 
@@ -1701,6 +2004,7 @@ if start_stream:
                 immediate_rendering=bool(radio_cfg['immediate_rendering']),
                 presentation_delay_us=int(radio_cfg['presentation_delay_ms'] * 1000),
                 qos_config=QOS_PRESET_MAP[radio_cfg['qos_preset']],
+                advertising_tx_power=int(radio_cfg.get('tx_power', TX_POWER_DEFAULT)),
                 bigs=bigs
             )
 
@@ -1736,6 +2040,7 @@ if start_stream:
             immediate_rendering=immediate_rendering,
             presentation_delay_us=int(presentation_delay_ms * 1000),
             qos_config=QOS_PRESET_MAP[qos_preset],
+            advertising_tx_power=tx_power,
             bigs=[
                 auracast_config.AuracastBigConfig(
                     code=(stream_passwort.strip() or None),

src/auracast/server/multicast_server.py

@@ -10,6 +10,7 @@ from datetime import datetime
 import asyncio
 import random
 import subprocess
+import threading
 from dotenv import load_dotenv
 
 from fastapi import FastAPI, HTTPException
@@ -208,6 +209,28 @@ multicaster1: multicast_control.Multicaster | None = None
 multicaster2: multicast_control.Multicaster | None = None
 _stream_lock = asyncio.Lock()  # serialize initialize/stop_audio on API side
 
+# BLE / audio event loop – set in __main__ before uvicorn starts.
+# All coroutines that touch Bumble objects or the audio pipeline MUST run
+# on this loop.  HTTP handlers call _on_ble_loop() to cross into it.
+_ble_loop: asyncio.AbstractEventLoop | None = None
+
+
+async def _on_ble_loop(coro):
+    """Submit *coro* to the BLE event loop and await the result.
+
+    Called from uvicorn's event loop.  Bridges HTTP handler coroutines into
+    the isolated BLE loop so that serial I/O (serial_asyncio / HCI) and the
+    audio pipeline are never preempted by HTTP accept/read/write callbacks.
+
+    asyncio.run_coroutine_threadsafe() schedules the coroutine on _ble_loop
+    (thread-safe), returning a concurrent.futures.Future.
+    asyncio.wrap_future() adapts that into an asyncio.Future so the caller
+    can simply `await` it inside uvicorn's loop.
+    """
+    assert _ble_loop is not None, "BLE loop not yet initialised"
+    future = asyncio.run_coroutine_threadsafe(coro, _ble_loop)
+    return await asyncio.wrap_future(future)
+
 
 async def _init_i2c_on_startup() -> None:
     # Ensure i2c-dev kernel module is loaded (required for /dev/i2c-* access)
@@ -422,6 +445,11 @@ async def init_radio(transport: str, conf: auracast_config.AuracastConfigGroup,
         first_source = conf.bigs[0].audio_source if conf.bigs else ''
         input_device_name = None
         audio_mode_persist = 'Demo'
+        # Capture original per-BIG device names before transformation
+        original_input_devices = [
+            big.audio_source.split(':', 1)[1] if (isinstance(big.audio_source, str) and big.audio_source.startswith('device:')) else None
+            for big in conf.bigs
+        ]
         if any(isinstance(b.audio_source, str) and b.audio_source.startswith('device:') for b in conf.bigs):
             if isinstance(first_source, str) and first_source.startswith('device:'):
                 input_device_name = first_source.split(':', 1)[1] if ':' in first_source else None
@@ -564,6 +592,13 @@ async def init_radio(transport: str, conf: auracast_config.AuracastConfigGroup,
         demo_count = sum(1 for big in conf.bigs if isinstance(big.audio_source, str) and big.audio_source.startswith('file:'))
         demo_rate = int(conf.auracast_sampling_rate_hz or 0)
         demo_type = None
+        demo_sources = [
+            str(b.audio_source)
+            for b in conf.bigs
+            if isinstance(b.audio_source, str) and b.audio_source.startswith('file:')
+        ]
+        is_demo_tone = bool(demo_sources) and all('test_tone_1k_' in src for src in demo_sources)
+        demo_content = '1 kHz test tone' if is_demo_tone else 'Program material'
         if demo_count > 0 and demo_rate > 0:
             if demo_rate in (48000, 24000, 16000):
                 demo_type = f"{demo_count} × {demo_rate//1000}kHz"
@@ -574,6 +609,7 @@ async def init_radio(transport: str, conf: auracast_config.AuracastConfigGroup,
             'languages': [big.language for big in conf.bigs],
             'audio_mode': audio_mode_persist,
             'input_device': input_device_name,
+            'input_devices': original_input_devices,
             'program_info': [getattr(big, 'program_info', None) for big in conf.bigs],
             'gain': [getattr(big, 'input_gain', 1.0) for big in conf.bigs],
             'auracast_sampling_rate_hz': conf.auracast_sampling_rate_hz,
@@ -585,13 +621,15 @@ async def init_radio(transport: str, conf: auracast_config.AuracastConfigGroup,
             'analog_stereo_mode': getattr(conf.bigs[0], 'analog_stereo_mode', False) if conf.bigs else False,
             'analog_gain_db_left': getattr(conf, 'analog_gain_db_left', 0.0),
             'analog_gain_db_right': getattr(conf, 'analog_gain_db_right', 0.0),
+            'advertising_tx_power': getattr(conf, 'advertising_tx_power', 8),
             'stream_password': (conf.bigs[0].code if conf.bigs and getattr(conf.bigs[0], 'code', None) else None),
             'big_ids': [getattr(big, 'id', DEFAULT_BIG_ID) for big in conf.bigs],
             'big_random_addresses': [getattr(big, 'random_address', DEFAULT_RANDOM_ADDRESS) for big in conf.bigs],
             'demo_total_streams': demo_count,
             'demo_stream_type': demo_type,
+            'demo_content': demo_content,
             'is_streaming': auto_started,
-            'demo_sources': [str(b.audio_source) for b in conf.bigs if isinstance(b.audio_source, str) and b.audio_source.startswith('file:')],
+            'demo_sources': demo_sources,
         }
         return mc, persisted
     except HTTPException:
@@ -602,7 +640,10 @@ async def init_radio(transport: str, conf: auracast_config.AuracastConfigGroup,
 
 @app.post("/init")
 async def initialize(conf: auracast_config.AuracastConfigGroup):
-    """Initializes the primary broadcaster on the streamer thread."""
+    """Initializes the primary broadcaster on the BLE loop."""
+    return await _on_ble_loop(_initialize_impl(conf))
+
+async def _initialize_impl(conf: auracast_config.AuracastConfigGroup):
     async with _stream_lock:
         global multicaster1, global_config_group
         mc, persisted = await init_radio(TRANSPORT1, conf, multicaster1)
@@ -612,7 +653,10 @@ async def initialize(conf: auracast_config.AuracastConfigGroup):
 
 @app.post("/init2")
 async def initialize2(conf: auracast_config.AuracastConfigGroup):
-    """Initializes the secondary broadcaster on the streamer thread."""
+    """Initializes the secondary broadcaster on the BLE loop."""
+    return await _on_ble_loop(_initialize2_impl(conf))
+
+async def _initialize2_impl(conf: auracast_config.AuracastConfigGroup):
     async with _stream_lock:
         global multicaster2
         mc, persisted = await init_radio(TRANSPORT2, conf, multicaster2)
@@ -631,7 +675,11 @@ async def set_led_enabled(body: dict):
 
 @app.post("/stop_audio")
 async def stop_audio():
-    """Stops streaming on both multicaster1 and multicaster2 (worker thread)."""
+    """Stops streaming on both multicasters via the BLE loop."""
+    return await _on_ble_loop(_stop_audio_impl())
+
+async def _stop_audio_impl():
+    """Runs on BLE loop: stops all streamers and persists is_streaming=False."""
     try:
         was_running = await _stop_all()
 
@@ -681,9 +729,9 @@ async def set_adc_gain(payload: dict):
 
 @app.post("/stream_lc3")
 async def send_audio(audio_data: dict[str, str]):
-    """Sends a block of pre-coded LC3 audio via the worker."""
+    """Sends a block of pre-coded LC3 audio via the BLE loop."""
     try:
-        await _stream_lc3(audio_data, list(global_config_group.bigs))
+        await _on_ble_loop(_stream_lc3(audio_data, list(global_config_group.bigs)))
         return {"status": "audio_sent"}
     except Exception as e:
         raise HTTPException(status_code=500, detail=str(e))
@@ -755,11 +803,12 @@ async def _autostart_from_settings():
         big_ids = settings.get('big_ids') or []
         big_addrs = settings.get('big_random_addresses') or []
         stream_password = settings.get('stream_password')
+        tx_power = int(settings.get('advertising_tx_power', 8))
         original_ts = settings.get('timestamp')
         previously_streaming = bool(settings.get('is_streaming'))
 
         log.info(
-            "[AUTOSTART][PRIMARY] loaded settings: previously_streaming=%s audio_mode=%s rate=%s octets=%s pres_delay=%s qos_preset=%s immediate_rendering=%s assisted_listening_stream=%s demo_sources=%s",
+            "[AUTOSTART][PRIMARY] loaded settings: previously_streaming=%s audio_mode=%s rate=%s octets=%s pres_delay=%s qos_preset=%s immediate_rendering=%s assisted_listening_stream=%s tx_power=%+d dBm demo_sources=%s",
             previously_streaming,
             audio_mode,
             rate,
@@ -768,6 +817,7 @@ async def _autostart_from_settings():
             saved_qos_preset,
             immediate_rendering,
             assisted_listening_stream,
+            tx_power,
             (settings.get('demo_sources') or []),
         )
 
@@ -817,6 +867,7 @@ async def _autostart_from_settings():
                 immediate_rendering=immediate_rendering,
                 assisted_listening_stream=assisted_listening_stream,
                 presentation_delay_us=pres_delay if pres_delay is not None else 40000,
+                advertising_tx_power=tx_power,
                 bigs=bigs,
             )
             # Set num_bis for stereo mode if needed
@@ -886,6 +937,7 @@ async def _autostart_from_settings():
                     presentation_delay_us=pres_delay if pres_delay is not None else 40000,
                     analog_gain_db_left=settings.get('analog_gain_db_left', 0.0),
                     analog_gain_db_right=settings.get('analog_gain_db_right', 0.0),
+                    advertising_tx_power=tx_power,
                     bigs=bigs,
                 )
                 # Set num_bis for stereo mode if needed
@@ -921,10 +973,11 @@ async def _autostart_from_settings():
         big_ids = settings.get('big_ids') or []
         big_addrs = settings.get('big_random_addresses') or []
         stream_password = settings.get('stream_password')
+        tx_power = int(settings.get('advertising_tx_power', 8))
         original_ts = settings.get('timestamp')
         previously_streaming = bool(settings.get('is_streaming'))
         log.info(
-            "[AUTOSTART][SECONDARY] loaded settings: previously_streaming=%s audio_mode=%s rate=%s octets=%s pres_delay=%s qos_preset=%s immediate_rendering=%s assisted_listening_stream=%s demo_sources=%s",
+            "[AUTOSTART][SECONDARY] loaded settings: previously_streaming=%s audio_mode=%s rate=%s octets=%s pres_delay=%s qos_preset=%s immediate_rendering=%s assisted_listening_stream=%s tx_power=%+d dBm demo_sources=%s",
             previously_streaming,
             audio_mode,
             rate,
@@ -933,6 +986,7 @@ async def _autostart_from_settings():
             saved_qos_preset,
             immediate_rendering,
             assisted_listening_stream,
+            tx_power,
             (settings.get('demo_sources') or []),
         )
         if not previously_streaming:
@@ -972,6 +1026,7 @@ async def _autostart_from_settings():
                 immediate_rendering=immediate_rendering,
                 assisted_listening_stream=assisted_listening_stream,
                 presentation_delay_us=pres_delay if pres_delay is not None else 40000,
+                advertising_tx_power=tx_power,
                 bigs=bigs,
             )
             conf.qos_config = QOS_PRESET_MAP.get(saved_qos_preset, QOS_PRESET_MAP["Fast"])
@@ -1041,6 +1096,7 @@ async def _autostart_from_settings():
                     presentation_delay_us=pres_delay if pres_delay is not None else 40000,
                     analog_gain_db_left=settings.get('analog_gain_db_left', 0.0),
                     analog_gain_db_right=settings.get('analog_gain_db_right', 0.0),
+                    advertising_tx_power=tx_power,
                     bigs=bigs,
                 )
                 conf.qos_config = QOS_PRESET_MAP.get(saved_qos_preset, QOS_PRESET_MAP["Fast"])
@@ -1058,6 +1114,19 @@ async def _autostart_from_settings():
     await do_primary()
     await do_secondary()
 
+async def _ble_startup():
+    """I2C init, ADC level reset, and autostart task scheduling on the BLE loop.
+
+    Bridged from _startup_autostart_event() so that these async subprocess
+    calls and the long-lived autostart coroutine all run on _ble_loop, never
+    on uvicorn's HTTP loop.
+    """
+    await _init_i2c_on_startup()
+    await _set_adc_level(0.0, 0.0)
+    log.info("[STARTUP] Scheduling autostart task on BLE loop")
+    asyncio.create_task(_autostart_from_settings())
+
+
 @app.on_event("startup")  
 async def _startup_autostart_event():
     # Spawn the autostart task without blocking startup
@@ -1078,12 +1147,11 @@ async def _startup_autostart_event():
     # Hydrate settings cache once to avoid disk I/O during /status
     _load_led_settings()
     _init_settings_cache_from_disk()
-    await _init_i2c_on_startup()
-    # Ensure ADC mixer level is set at startup (default 0 dB)
-    await _set_adc_level(0.0, 0.0)
     refresh_pw_cache()
-    log.info("[STARTUP] Scheduling autostart task")
-    asyncio.create_task(_autostart_from_settings())
+    # I2C init, ADC setup and the autostart task must run on the BLE loop so
+    # they share the same event loop as the Bumble HCI transport.
+    log.info("[STARTUP] Bridging I2C init and autostart to BLE loop")
+    asyncio.run_coroutine_threadsafe(_ble_startup(), _ble_loop)
 
 @app.get("/audio_inputs_pw_usb")
 async def audio_inputs_pw_usb():
@@ -1154,6 +1222,9 @@ async def refresh_audio_devices():
 @app.post("/shutdown")
 async def shutdown():
     """Stops broadcasting and releases all audio/Bluetooth resources."""
+    return await _on_ble_loop(_shutdown_impl())
+
+async def _shutdown_impl():
     try:
         await _stop_all()
         return {"status": "stopped"}
@@ -1166,6 +1237,9 @@ async def system_reboot():
 
     Requires the service user to have passwordless sudo permissions to run 'reboot'.
     """
+    return await _on_ble_loop(_system_reboot_impl())
+
+async def _system_reboot_impl():
     try:
         # Best-effort: stop any active streaming cleanly WITHOUT persisting state
         try:
@@ -1189,46 +1263,26 @@ async def system_reboot():
 
 @app.post("/restart_dep")
 async def restart_dep():
-    """Restart DEP by running dep.sh stop then dep.sh start in the dep directory.
+    """Restart DEP via systemctl restart dep.service.
     
-    Requires the service user to have passwordless sudo permissions to run dep.sh.
+    Requires the service user to have passwordless sudo permissions for systemctl.
     """
     try:
-        # Get the dep directory path (dep.sh is in dante_package subdirectory)
-        dep_dir = os.path.join(os.path.dirname(__file__), '..', '..', 'dep', 'dante_package')
-        
-        # Run dep.sh stop first
-        log.info("Stopping DEP...")
-        stop_process = await asyncio.create_subprocess_exec(
-            "sudo", "bash", "dep.sh", "stop",
-            cwd=dep_dir,
+        log.info("Restarting DEP via systemctl...")
+        proc = await asyncio.create_subprocess_exec(
+            "sudo", "systemctl", "restart", "dep.service",
             stdout=asyncio.subprocess.PIPE,
             stderr=asyncio.subprocess.PIPE
         )
-        stop_stdout, stop_stderr = await stop_process.communicate()
+        stdout, stderr = await proc.communicate()
 
-        if stop_process.returncode != 0:
-            error_msg = stop_stderr.decode() if stop_stderr else "Unknown error"
-            log.error(f"Failed to stop DEP: {error_msg}")
-            raise HTTPException(status_code=500, detail=f"Failed to stop DEP: {error_msg}")
-        
-        # Run dep.sh start after stop succeeds
-        log.info("Starting DEP...")
-        start_process = await asyncio.create_subprocess_exec(
-            "sudo", "bash", "dep.sh", "start",
-            cwd=dep_dir,
-            stdout=asyncio.subprocess.PIPE,
-            stderr=asyncio.subprocess.PIPE
-        )
-        start_stdout, start_stderr = await start_process.communicate()
-        
-        if start_process.returncode == 0:
+        if proc.returncode == 0:
             log.info("DEP restarted successfully")
             return {"status": "success", "message": "DEP restarted successfully"}
         else:
-            error_msg = start_stderr.decode() if start_stderr else "Unknown error"
-            log.error(f"Failed to start DEP: {error_msg}")
-            raise HTTPException(status_code=500, detail=f"Failed to start DEP: {error_msg}")
+            error_msg = stderr.decode() if stderr else "Unknown error"
+            log.error(f"Failed to restart DEP: {error_msg}")
+            raise HTTPException(status_code=500, detail=f"Failed to restart DEP: {error_msg}")
 
     except HTTPException:
         raise
@@ -1322,6 +1376,9 @@ async def check_update():
 @app.post("/system_update")
 async def system_update():
     """Update application: git pull main branch (latest tag), poetry install, restart services."""
+    return await _on_ble_loop(_system_update_impl())
+
+async def _system_update_impl():
     try:
         # Best-effort: stop any active streaming cleanly
         try:
@@ -1789,5 +1846,170 @@ if __name__ == '__main__':
         level=os.environ.get('LOG_LEVEL', log.INFO),
         format='%(module)s.py:%(lineno)d %(levelname)s: %(message)s'
     )
+
+    # ── GIL switch interval ─────────────────────────────────────────────────
+    # CPython releases the GIL every sys.getswitchinterval() seconds (default
+    # 5 ms).  The audio pipeline fires every 10 ms, so a 5 ms granularity
+    # means up to half a frame period can be wasted waiting for the GIL.
+    # Reducing to 1 ms gives the BLE thread much tighter access.
+    import sys
+    sys.setswitchinterval(0.001)
+    log.info("GIL switch interval set to 1 ms")
+
+    # ── BLE / audio event loop ──────────────────────────────────────────────
+    # Bumble (serial_asyncio / HCI) and the audio pipeline run exclusively on
+    # this loop.  Uvicorn's HTTP accept/read/write callbacks run on a separate
+    # asyncio loop in the main thread, so they can never stall BLE advertising
+    # or audio encoding.
+    #
+    # Route handlers that touch Bumble objects call _on_ble_loop(), which uses
+    # asyncio.run_coroutine_threadsafe() + asyncio.wrap_future() to submit the
+    # coroutine to _ble_loop and await the result back in uvicorn's loop.
+    # Hot-path read-only endpoints (/status, /audio_level*) access
+    # multicaster state directly – Python's GIL makes attribute reads safe.
+
+    def _pthread_sched_lib():
+        """Return a ctypes handle with correctly typed pthread scheduling symbols.
+
+        Uses RTLD_DEFAULT (ctypes.CDLL(None)) to resolve symbols from all
+        currently loaded shared libraries.  This handles both:
+          - glibc < 2.34: pthread_self/pthread_setschedparam live in libpthread.so.0
+          - glibc >= 2.34: pthreads merged into libc.so.6
+        using find_library("c") would miss libpthread on older glibc and cause
+        a NULL function pointer → SEGV when called.
+
+        Explicit restype/argtypes are mandatory: pthread_t is c_ulong (64-bit
+        on ARM64/x86-64) but ctypes defaults to c_int (32-bit), truncating
+        the thread handle and causing a SEGV inside pthread_setschedparam.
+        """
+        import ctypes
+
+        SCHED_FIFO  = 1
+        SCHED_OTHER = 0
+
+        class SchedParam(ctypes.Structure):
+            _fields_ = [("sched_priority", ctypes.c_int)]
+
+        lib = ctypes.CDLL(None, use_errno=True)  # RTLD_DEFAULT
+
+        lib.pthread_self.restype  = ctypes.c_ulong
+        lib.pthread_self.argtypes = []
+
+        lib.pthread_getschedparam.restype  = ctypes.c_int
+        lib.pthread_getschedparam.argtypes = [
+            ctypes.c_ulong,
+            ctypes.POINTER(ctypes.c_int),
+            ctypes.POINTER(SchedParam),
+        ]
+        lib.pthread_setschedparam.restype  = ctypes.c_int
+        lib.pthread_setschedparam.argtypes = [
+            ctypes.c_ulong,
+            ctypes.c_int,
+            ctypes.POINTER(SchedParam),
+        ]
+        return lib, SchedParam, SCHED_FIFO, SCHED_OTHER
+
+    def _configure_ble_thread_scheduling():
+        """Confirm or establish SCHED_FIFO for the BLE/audio thread.
+
+        When launched via the systemd unit (CPUSchedulingPolicy=fifo), new
+        threads inherit the process RT policy automatically – just log and
+        return.  When run directly (development), attempt to elevate to
+        SCHED_FIFO/30 (requires CAP_SYS_NICE), falling back gracefully.
+        """
+        import ctypes
+        try:
+            lib, SchedParam, SCHED_FIFO, _ = _pthread_sched_lib()
+            tid     = lib.pthread_self()
+            policy  = ctypes.c_int(-1)
+            param   = SchedParam(0)
+            lib.pthread_getschedparam(tid, ctypes.byref(policy), ctypes.byref(param))
+
+            if policy.value == SCHED_FIFO:
+                log.info("[BLE-LOOP] Already SCHED_FIFO priority=%d (inherited from systemd)",
+                         param.sched_priority)
+                return
+
+            param.sched_priority = 30
+            ret = lib.pthread_setschedparam(tid, SCHED_FIFO, ctypes.byref(param))
+            if ret == 0:
+                log.info("[BLE-LOOP] SCHED_FIFO priority=30 set")
+            else:
+                err = ctypes.get_errno()
+                log.warning("[BLE-LOOP] SCHED_FIFO failed (errno=%d: %s) – "
+                            "use systemd CPUSchedulingPolicy=fifo or grant CAP_SYS_NICE",
+                            err, os.strerror(err))
+                try:
+                    os.setpriority(os.PRIO_PROCESS, 0,
+                                   os.getpriority(os.PRIO_PROCESS, 0) - 5)
+                except PermissionError:
+                    pass
+        except Exception as exc:
+            log.warning("[BLE-LOOP] Scheduling setup error: %s", exc)
+
+    def _configure_http_thread_scheduling():
+        """Demote the HTTP (uvicorn) thread to SCHED_OTHER + nice=+10.
+
+        When systemd sets CPUSchedulingPolicy=fifo, every thread in the
+        process – including uvicorn's main loop – inherits SCHED_FIFO.
+        We demote the HTTP thread back to SCHED_OTHER so the BLE thread
+        always wins CPU arbitration when both are runnable.
+        Lowering scheduling policy never requires special privileges.
+        """
+        import ctypes
+        try:
+            lib, SchedParam, SCHED_FIFO, SCHED_OTHER = _pthread_sched_lib()
+            tid    = lib.pthread_self()
+            policy = ctypes.c_int(-1)
+            param  = SchedParam(0)
+            lib.pthread_getschedparam(tid, ctypes.byref(policy), ctypes.byref(param))
+
+            if policy.value == SCHED_FIFO:
+                param.sched_priority = 0
+                ret = lib.pthread_setschedparam(tid, SCHED_OTHER, ctypes.byref(param))
+                if ret == 0:
+                    log.info("[HTTP] Demoted SCHED_FIFO → SCHED_OTHER")
+                else:
+                    err = ctypes.get_errno()
+                    log.warning("[HTTP] Could not demote from SCHED_FIFO (errno=%d)", err)
+            else:
+                log.info("[HTTP] Already SCHED_OTHER, no demotion needed")
+        except Exception as exc:
+            log.warning("[HTTP] Scheduling demotion error: %s", exc)
+
+        try:
+            os.nice(10)
+            log.info("[HTTP] nice=+10 (lower priority)")
+        except Exception as exc:
+            log.debug("[HTTP] os.nice: %s", exc)
+
+    _ble_loop_ready = threading.Event()
+
+    def _run_ble_loop():
+        # Confirm or establish RT scheduling before entering the event loop.
+        _configure_ble_thread_scheduling()
+
+        async def _ble_runner():
+            global _ble_loop
+            _ble_loop = asyncio.get_running_loop()
+            _ble_loop_ready.set()
+            # Keep the loop alive; it is stopped when the process exits because
+            # this is a daemon thread.
+            await asyncio.Event().wait()
+
+        asyncio.run(_ble_runner())
+
+    _ble_thread = threading.Thread(target=_run_ble_loop, name="ble-loop", daemon=True)
+    _ble_thread.start()
+    if not _ble_loop_ready.wait(timeout=5):
+        log.error("BLE event loop failed to start within 5 s – aborting")
+        raise RuntimeError("BLE event loop startup timeout")
+    log.info("BLE event loop started on thread '%s'", _ble_thread.name)
+
+    # ── HTTP / uvicorn event loop (main thread) ─────────────────────────────
+    # Demote the HTTP thread from SCHED_FIFO (if set by systemd) to
+    # SCHED_OTHER + nice=+10 so the BLE thread always preempts it.
+    _configure_http_thread_scheduling()
+
     # Bind to localhost only for security: prevents network access, only frontend on same machine can connect
     uvicorn.run(app, host="127.0.0.1", port=5000, access_log=False)

src/auracast/utils/read_lc3_file.py

@@ -21,12 +21,12 @@ def read_lc3_file(filepath):
         logging.info('frame_duration %s', frame_duration)
         logging.info('stream_length %s', stream_length)
 
-        lc3_bytes= b''
+        chunks = []
         while True:
             b = f_lc3.read(2)
             if b == b'':
                 break
             lc3_frame_size = struct.unpack('=H', b)[0]
-            lc3_bytes += f_lc3.read(lc3_frame_size)
+            chunks.append(f_lc3.read(lc3_frame_size))
 
-        return lc3_bytes
+        return b''.join(chunks)

src/dep/dante_package/dante_data/activation/.gitkeep

@@ -0,0 +1 @@
+Placeholder file to have the activation folder available, otherwise dante activation script fails with 'Unable to write'.

src/dep/dante_package/dante_data/capability/dante.json

@@ -1,5 +1,5 @@
 {
-	"trialMode": true,
+	"trialMode": false,
 	"$schema": "./dante.json_schema.json",
 	"platform":
 	{
@@ -16,7 +16,7 @@
 				48000
 			],
 		"samplesPerPeriod" : 16,
-		"periodsPerBuffer" : 300,
+		"periodsPerBuffer" : 150,
 		"networkLatencyMinMs" : 2,
 		"networkLatencyDefaultMs" : 5,
 		"supportedEncodings" :
@@ -24,7 +24,10 @@
 				"PCM16"
 			],
 		"defaultEncoding" : "PCM16",
-		"numDepCores" : 1
+		"numDepCores" : 
+			[
+				3
+			]
 	},
 	"network" :
 	{
@@ -50,31 +53,32 @@
 	"alsaAsrc":
 	{
 		"enableAlsaAsrc": true,
+		"cpuAffinity": 3,
 		"deviceConfigurations": [
 			{
-			"deviceIdentifier": "hw:0,0",
+			"deviceIdentifier": "hw:6,0,0",
 			"direction": "playback",
 			"bitDepth": 16,
 			"numOpenChannels": 6,
 			"alsaChannelRange": "0-5",
 			"danteChannelRange": "0-5",
-			"bufferSize": 4800,
+			"bufferSize": 960,
 			"samplesPerPeriod": 16
 			}
 		]
 	},
 	"product" :
 	{
-		"manfId" : "Audinate",
-		"manfName" : "Audinate Pty Ltd",
-		"modelId" : "OEMDEP",
-		"modelName" : "Linux Dante Embedded Platform",
+		"manfId" : "SummitFC",
+		"manfName" : "Summitwave FlexCo",
+		"modelId" : "TX",
+		"modelName" : "Summitwave TX",
 		"modelVersion" :
 			{
-				"major" : 9,
-				"minor" : 9,
-				"bugfix" : 99
+				"major" : 1,
+				"minor" : 0,
+				"bugfix" : 0
 			},
-		"devicePrefix" : "DEP"
+		"devicePrefix" : "SW-TX"
 	}
 }

src/openocd/merged.hex.version

@@ -0,0 +1,8 @@
+# Provenance of src/openocd/merged.hex — generated by update_firmware.sh. Do not edit by hand.
+firmware_commit: 52d034e58e42f15449b4d026e056ed99d10999d9
+firmware_describe: 52d034e
+firmware_branch: HEAD
+preset: build_nrf54_radio0_radio1
+ncs_version: v3.0.2
+merged_hex_sha256: 4d7779191d08aaefe45f04c2689f3ecbe49688c8e78c7fa9a40550d545df8b17
+exported_utc: 2026-07-13T12:02:55Z

src/openocd/update_firmware.sh

@@ -0,0 +1,161 @@
+#!/bin/bash
+#
+# update_firmware.sh — build (optional) and export the beacon firmware image.
+#
+# Copies the sysbuild `merged.hex` produced from the `firmware/` submodule to
+# src/openocd/merged.hex (the committed artifact the RPi flashes via flash.sh)
+# and records its provenance in src/openocd/merged.hex.version.
+#
+# This runs on a DEV MACHINE that has the nRF Connect SDK (~/ncs) — never on a
+# beacon device. Devices only ever consume the committed merged.hex.
+#
+# Usage:
+#   src/openocd/update_firmware.sh [--build] [--preset NAME] [--ncs-version VER] [--force]
+#
+#   (default)          Export merged.hex from an existing build dir.
+#   --build            Configure + build the sysbuild image from scratch (a true
+#                      one-shot), then export. Uses the nRF Connect SDK via
+#                      `nrfutil toolchain-manager launch` — no manual env setup.
+#   --preset NAME      Preset in firmware/CMakePresets.json to build/export
+#                      (default: build_nrf54_radio0_radio1). BOARD and the
+#                      conf/overlay files are read straight from that preset.
+#   --ncs-version VER  nRF Connect SDK version to build with (default: v3.0.2).
+#                      West workspace is $HOME/ncs/VER unless $NCS_WORKSPACE set.
+#   --force            Export even if the firmware submodule working tree is dirty.
+#
+# Example (rebuild the production image from the pinned firmware commit and export):
+#   git submodule update --init firmware
+#   src/openocd/update_firmware.sh --build
+#
+# Note: merged.hex is a *sysbuild* output. A plain `cmake --preset` configure
+# only produces zephyr/zephyr.hex — this script deliberately refuses to fall
+# back to that, so the exported artifact is always the real merged image.
+
+set -euo pipefail
+
+PRESET="build_nrf54_radio0_radio1"
+NCS_VERSION="v3.0.2"
+DO_BUILD=0
+FORCE=0
+
+usage() { awk 'NR>1 && /^#/ {sub(/^# ?/,""); print; next} NR>1 {exit}' "$0"; exit "${1:-1}"; }
+
+while [[ $# -gt 0 ]]; do
+  case "$1" in
+    --build)       DO_BUILD=1 ;;
+    --preset)      shift; PRESET="${1:?--preset needs a value}" ;;
+    --ncs-version) shift; NCS_VERSION="${1:?--ncs-version needs a value}" ;;
+    --force)       FORCE=1 ;;
+    -h|--help)     usage 0 ;;
+    *) echo "Unknown argument: $1" >&2; usage ;;
+  esac
+  shift
+done
+
+# Repo root = two levels up from this script (src/openocd/ -> repo root).
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+ROOT="$(cd "$SCRIPT_DIR/../.." && pwd)"
+FIRMWARE_DIR="$ROOT/firmware"
+BUILD_DIR="$FIRMWARE_DIR/$PRESET"
+SRC_HEX="$BUILD_DIR/merged.hex"
+DEST_HEX="$ROOT/src/openocd/merged.hex"
+VERSION_FILE="$ROOT/src/openocd/merged.hex.version"
+
+die() { echo "[update_firmware] ERROR: $*" >&2; exit 1; }
+
+# 1. Submodule present and populated?
+[[ -f "$FIRMWARE_DIR/.git" || -d "$FIRMWARE_DIR/.git" ]] \
+  || die "firmware submodule not initialised. Run: git submodule update --init firmware"
+git -C "$FIRMWARE_DIR" rev-parse HEAD >/dev/null 2>&1 \
+  || die "firmware submodule has no checkout. Run: git submodule update --init firmware"
+
+# 2. Optional sysbuild build (configure + compile) via the NCS toolchain manager.
+#    BOARD and the conf/overlay files come straight from firmware/CMakePresets.json,
+#    so this stays in sync with the preset the nRF Connect VS Code extension uses.
+if [[ "$DO_BUILD" == "1" ]]; then
+  command -v nrfutil >/dev/null 2>&1 \
+    || die "'nrfutil' not found. Install the nRF Connect SDK toolchain manager first."
+  PRESETS_JSON="$FIRMWARE_DIR/CMakePresets.json"
+  [[ -f "$PRESETS_JSON" ]] || die "no CMakePresets.json in $FIRMWARE_DIR"
+
+  # Read BOARD / CONF_FILE / EXTRA_CONF_FILE / DTC_OVERLAY_FILE from the preset.
+  preset_vars="$(python3 - "$PRESETS_JSON" "$PRESET" <<'PY'
+import json, sys
+path, preset = sys.argv[1], sys.argv[2]
+cfgs = {c["name"]: c for c in json.load(open(path)).get("configurePresets", [])}
+if preset not in cfgs:
+    sys.exit(f"preset '{preset}' not found in {path}")
+cv = cfgs[preset].get("cacheVariables", {})
+def g(k):
+    v = cv.get(k)
+    return (v.get("value") if isinstance(v, dict) else v) or ""
+for k in ("BOARD", "CONF_FILE", "EXTRA_CONF_FILE", "DTC_OVERLAY_FILE"):
+    print(f"{k}={g(k)}")
+PY
+)" || die "failed to parse preset '$PRESET' from CMakePresets.json"
+  # Import without eval — values (e.g. EXTRA_CONF_FILE) contain ';'.
+  PRESET_BOARD=""; PRESET_CONF_FILE=""; PRESET_EXTRA_CONF_FILE=""; PRESET_DTC_OVERLAY_FILE=""
+  while IFS='=' read -r _k _v; do
+    case "$_k" in
+      BOARD)            PRESET_BOARD="$_v" ;;
+      CONF_FILE)        PRESET_CONF_FILE="$_v" ;;
+      EXTRA_CONF_FILE)  PRESET_EXTRA_CONF_FILE="$_v" ;;
+      DTC_OVERLAY_FILE) PRESET_DTC_OVERLAY_FILE="$_v" ;;
+    esac
+  done <<< "$preset_vars"
+  [[ -n "$PRESET_BOARD" ]] || die "preset '$PRESET' defines no BOARD"
+
+  WORKSPACE="${NCS_WORKSPACE:-$HOME/ncs/$NCS_VERSION}"
+  [[ -d "$WORKSPACE/.west" ]] \
+    || die "no west workspace at '$WORKSPACE' (set \$NCS_WORKSPACE or pass --ncs-version)."
+
+  # Assemble the -D flags. CONF_FILE=prj.conf is west's default, so omit it then.
+  DFLAGS=()
+  [[ -n "$PRESET_CONF_FILE" && "$PRESET_CONF_FILE" != "prj.conf" ]] && DFLAGS+=( "-DCONF_FILE=$PRESET_CONF_FILE" )
+  [[ -n "$PRESET_EXTRA_CONF_FILE" ]] && DFLAGS+=( "-DEXTRA_CONF_FILE=$PRESET_EXTRA_CONF_FILE" )
+  [[ -n "$PRESET_DTC_OVERLAY_FILE" ]] && DFLAGS+=( "-DDTC_OVERLAY_FILE=$PRESET_DTC_OVERLAY_FILE" )
+
+  # Build the inner command with each token shell-quoted (conf lists contain ';').
+  inner="cd $(printf %q "$WORKSPACE") && west build --sysbuild -p auto"
+  inner+=" -b $(printf %q "$PRESET_BOARD") -d $(printf %q "$BUILD_DIR") $(printf %q "$FIRMWARE_DIR") --"
+  for f in "${DFLAGS[@]}"; do inner+=" $(printf %q "$f")"; done
+
+  echo "[update_firmware] Building $PRESET (NCS $NCS_VERSION, board $PRESET_BOARD) ..."
+  echo "[update_firmware]   west build --sysbuild ${DFLAGS[*]}"
+  nrfutil toolchain-manager launch --ncs-version "$NCS_VERSION" -- bash -c "$inner" \
+    || die "west build failed."
+fi
+
+# 3. Require the sysbuild artifact (no silent zephyr.hex fallback).
+[[ -f "$SRC_HEX" ]] || die "no merged.hex at '$SRC_HEX'. Build '$PRESET' with sysbuild \
+(pass --build once the dir is configured), or point --preset at the right build dir."
+
+# 4. Clean-tree guard so the deployed hex maps to a real firmware commit.
+FW_DESCRIBE="$(git -C "$FIRMWARE_DIR" describe --always --dirty --tags 2>/dev/null || git -C "$FIRMWARE_DIR" rev-parse --short HEAD)"
+if [[ "$FW_DESCRIBE" == *-dirty && "$FORCE" != "1" ]]; then
+  die "firmware submodule working tree is dirty ($FW_DESCRIBE). Commit/stash it, or pass --force."
+fi
+
+# 5. Export.
+cp "$SRC_HEX" "$DEST_HEX"
+
+# 6. Provenance.
+FW_COMMIT="$(git -C "$FIRMWARE_DIR" rev-parse HEAD)"
+FW_BRANCH="$(git -C "$FIRMWARE_DIR" rev-parse --abbrev-ref HEAD 2>/dev/null || echo 'detached')"
+HEX_SHA="$(sha256sum "$DEST_HEX" | awk '{print $1}')"
+cat > "$VERSION_FILE" <<EOF
+# Provenance of src/openocd/merged.hex — generated by update_firmware.sh. Do not edit by hand.
+firmware_commit: $FW_COMMIT
+firmware_describe: $FW_DESCRIBE
+firmware_branch: $FW_BRANCH
+preset: $PRESET
+ncs_version: $NCS_VERSION
+merged_hex_sha256: $HEX_SHA
+exported_utc: $(date -u +%Y-%m-%dT%H:%M:%SZ)
+EOF
+
+echo "[update_firmware] Exported $SRC_HEX"
+echo "[update_firmware]       -> $DEST_HEX"
+echo "[update_firmware] firmware: $FW_DESCRIBE ($FW_COMMIT)"
+echo "[update_firmware] sha256:   $HEX_SHA"
+echo "[update_firmware] Now commit: git add src/openocd/merged.hex src/openocd/merged.hex.version firmware"

src/service/10-link-local-mgmt

@@ -0,0 +1,64 @@
+#!/bin/bash
+# NetworkManager dispatcher script: 10-link-local-mgmt
+#
+# Temporarily suppresses IPv4 link-local when a DHCP address is available,
+# using nmcli device modify (active session only, NOT saved to the profile).
+# The persistent profile always keeps ipv4.link-local=enabled so that
+# direct-connect (no DHCP) plug-ins always activate and trigger events.
+# Avahi is reloaded on each event — no /etc/avahi/hosts file, avahi uses
+# natural per-interface advertisement so each segment gets the right IP.
+#
+# Triggers: up, down, dhcp4-change on ethernet interfaces
+# Install to: /etc/NetworkManager/dispatcher.d/10-link-local-mgmt
+# Permissions: root:root 0755
+
+INTERFACE="$1"
+ACTION="$2"
+# Only handle ethernet interfaces
+if [[ ! "$INTERFACE" =~ ^eth ]]; then
+    exit 0
+fi
+
+reload_avahi() {
+    systemctl reload avahi-daemon 2>/dev/null || systemctl restart avahi-daemon 2>/dev/null
+    logger -t nm-link-local "[$INTERFACE] $ACTION — avahi reloaded"
+}
+
+case "$ACTION" in
+    up)
+        # On 'up' the interface may still carry a stale DHCP address from the previous
+        # session (NM hasn't cleaned it up yet). Reading ip-addr here is unreliable.
+        # Always re-enable link-local as a clean slate; let dhcp4-change suppress it
+        # later if a real DHCP lease is obtained.
+        logger -t nm-link-local "[$INTERFACE] Up — ensuring link-local active (clean slate)"
+        (sleep 2 && nmcli device modify "$INTERFACE" ipv4.link-local enabled 2>/dev/null \
+            && logger -t nm-link-local "[$INTERFACE] Link-local explicitly enabled on up") &
+        reload_avahi
+        ;;
+
+    dhcp4-change)
+        # dhcp4-change fires only when DHCP actually succeeds (new/renewed lease).
+        # At this point the DHCP IP is reliably present — safe to read and suppress link-local.
+        DHCP_IP=$(ip -4 addr show "$INTERFACE" 2>/dev/null \
+            | grep -oP '(?<=inet\s)\d+(\.\d+){3}' \
+            | grep -v '^127\.' \
+            | grep -v '^169\.254\.' \
+            | head -n1)
+
+        if [ -n "$DHCP_IP" ]; then
+            logger -t nm-link-local "[$INTERFACE] DHCP $DHCP_IP confirmed — suppressing link-local (session only)"
+            # Run in background after a delay — nmcli blocks on NM, which is waiting for
+            # this dispatcher to return, causing a deadlock if called synchronously.
+            (sleep 2 && nmcli device modify "$INTERFACE" ipv4.link-local disabled 2>/dev/null \
+                && logger -t nm-link-local "[$INTERFACE] Link-local suppressed for current session") &
+        fi
+        reload_avahi
+        ;;
+
+    down)
+        # NOTE: a carrier-change does NOT fully reset session-level 'device modify' state.
+        # The re-enable is therefore handled in the 'up' handler when no DHCP is detected.
+        logger -t nm-link-local "[$INTERFACE] Down — link-local will be re-enabled on next up without DHCP"
+        reload_avahi
+        ;;
+esac

src/service/auracast-frontend.service

@@ -10,6 +10,8 @@ WorkingDirectory=/home/caster/bumble-auracast/src/auracast/server
 ExecStart=/home/caster/bumble-auracast/src/auracast/server/start_frontend_https.sh
 Restart=on-failure
 Environment=LOG_LEVEL=INFO
+AllowedCPUs=0
+CPUAffinity=0
 
 [Install]
 WantedBy=multi-user.target

src/service/auracast-script.service

@@ -9,6 +9,8 @@ ExecStart=/home/caster/bumble-auracast/.venv/bin/python src/auracast/multicast_s
 Restart=on-failure
 Environment=PYTHONUNBUFFERED=1
 Environment=LOG_LEVEL=INFO
+AllowedCPUs=0
+CPUAffinity=0
 
 [Install]
 WantedBy=default.target

src/service/auracast-server.service

@@ -1,6 +1,7 @@
 [Unit]
 Description=Auracast Backend Server
-After=network.target
+After=network.target dep.service
+Wants=dep.service
 
 [Service]
 Type=simple
@@ -10,8 +11,10 @@ Restart=on-failure
 Environment=PYTHONUNBUFFERED=1
 Environment=LOG_LEVEL=INFO
 CPUSchedulingPolicy=fifo
-CPUSchedulingPriority=99
+CPUSchedulingPriority=10
 LimitRTPRIO=99
+AllowedCPUs=0,1,2
+CPUAffinity=0,1,2
 
 [Install]
 WantedBy=default.target

src/service/dep.service

@@ -0,0 +1,13 @@
+[Unit]
+Description=DEP (Dante Embedded Platform) Container
+After=network.target
+
+[Service]
+Type=oneshot
+RemainAfterExit=yes
+WorkingDirectory=/home/caster/bumble-auracast/src/dep/dante_package
+ExecStart=/bin/bash dep.sh start
+ExecStop=/bin/bash dep.sh stop
+
+[Install]
+WantedBy=multi-user.target

src/service/pipewire-aes67.service

@@ -9,6 +9,8 @@ ExecStartPre=/bin/sh -lc 'for i in $(seq 1 60); do ip route show default >/dev/n
 ExecStart=/usr/bin/pipewire-aes67 -c /home/caster/bumble-auracast/src/service/aes67/pipewire-aes67.conf
 Restart=always
 RestartSec=5s
+AllowedCPUs=0
+CPUAffinity=0
 # Avoid StartLimitHit on quick failures during boot; let RestartSec handle pacing
 StartLimitIntervalSec=0
 

src/service/ptp_aes67.service

@@ -6,6 +6,8 @@ After=network.target
 Type=simple
 ExecStart=/usr/sbin/ptp4l -i eth0 -f /home/caster/bumble-auracast/src/service/aes67/ptp_aes67_1.conf
 Restart=on-failure
+AllowedCPUs=0
+CPUAffinity=0
 StandardOutput=journal
 StandardError=journal
 

src/service/update_and_run_server_and_frontend.sh

@@ -8,30 +8,43 @@ set -e
 # Enable link-local for all wired ethernet connections
 while IFS=: read -r name type; do
     if [[ "$type" == *"ethernet"* ]]; then
-        echo "Enabling IPv4 link-local for connection: $name"
+        echo "Configuring connection: $name"
+        # link-local: always enabled so direct-connect (no DHCP) works immediately
         sudo nmcli connection modify "$name" ipv4.link-local enabled 2>/dev/null || echo "Failed to modify $name"
+        # may-fail=yes: do NOT tear down the connection when DHCP times out.
+        # Without this, NM declares ip-config-unavailable after the 45s DHCP timeout
+        # and enters a reconnect loop that causes ~1.5 min outages every ~45 seconds.
+        sudo nmcli connection modify "$name" ipv4.may-fail yes 2>/dev/null || echo "Failed to set may-fail on $name"
+        # Infinite DHCP timeout: NM keeps retrying DHCP in the background but never
+        # declares ip-config-unavailable. This prevents the 45s reconnect loop that
+        # kills the link-local address in direct-connect (no DHCP server) scenarios.
+        sudo nmcli connection modify "$name" ipv4.dhcp-timeout infinity 2>/dev/null || echo "Failed to set dhcp-timeout on $name"
         sudo nmcli connection up "$name" 2>/dev/null || echo "Failed to bring up $name"
     fi
 done < <(nmcli -t -f NAME,TYPE connection show)
 
-# Configure Avahi to prefer DHCP address over static fallback for mDNS
-# Get the DHCP-assigned IP (first non-localhost, non-192.168.42.10 IP)
-DHCP_IP=$(ip -4 addr show eth0 2>/dev/null | grep -oP '(?<=inet\s)\d+(\.\d+){3}' | grep -v '^127\.' | grep -v '^169\.254\.' | head -n1)
-HOSTNAME=$(hostname)
 
-if [ -n "$DHCP_IP" ]; then
-    echo "DHCP address detected: $DHCP_IP, configuring Avahi to prefer it for mDNS."
-    # Add entry to /etc/avahi/hosts to explicitly map hostname to DHCP IP
-    sudo mkdir -p /etc/avahi
-    echo "$DHCP_IP $HOSTNAME $HOSTNAME.local" | sudo tee /etc/avahi/hosts > /dev/null
-    # Restart avahi to apply the hosts file
-    sudo systemctl restart avahi-daemon
-else
-    echo "No DHCP address detected, mDNS will use link local"
-    # Remove hosts file to let Avahi advertise all IPs
-    sudo rm -f /etc/avahi/hosts
-    sudo systemctl restart avahi-daemon
-fi
+# Remove stale avahi hosts pin — this file overrides per-interface advertisement
+# and causes mDNS to always resolve to eth0's IP regardless of which interface
+# the query arrived on, breaking eth1 mDNS entirely.
+sudo rm -f /etc/avahi/hosts
+sudo systemctl restart avahi-daemon
+
+# Ensure Loopback is loaded with a fixed name and index 
+# Needed for dante
+# TODO image when we create the next image this should be part of it
+echo "options snd-aloop index=6 id=Loopback pcm_substreams=6" | sudo tee /etc/modprobe.d/snd-aloop.conf
+echo snd-aloop | sudo tee /etc/modules-load.d/snd-aloop.conf
+
+
+
+# Install NetworkManager dispatcher script for link-local / Avahi management
+sudo cp /home/caster/bumble-auracast/src/service/10-link-local-mgmt /etc/NetworkManager/dispatcher.d/10-link-local-mgmt
+sudo chown root:root /etc/NetworkManager/dispatcher.d/10-link-local-mgmt
+sudo chmod 755 /etc/NetworkManager/dispatcher.d/10-link-local-mgmt
+
+# Copy system service file for DEP
+sudo cp /home/caster/bumble-auracast/src/service/dep.service /etc/systemd/system/dep.service
 
 # Copy system service file for frontend
 sudo cp /home/caster/bumble-auracast/src/service/auracast-frontend.service /etc/systemd/system/auracast-frontend.service
@@ -40,20 +53,25 @@ sudo cp /home/caster/bumble-auracast/src/service/auracast-frontend.service /etc/
 mkdir -p /home/caster/.config/systemd/user
 cp /home/caster/bumble-auracast/src/service/auracast-server.service /home/caster/.config/systemd/user/auracast-server.service
 
-# Reload systemd for frontend
+# Reload systemd for frontend and dep
 sudo systemctl daemon-reload
 # Reload user systemd for server
 systemctl --user daemon-reload
 
+# Enable DEP to start on boot (system)
+sudo systemctl enable dep.service
 # Enable frontend to start on boot (system)
 sudo systemctl enable auracast-frontend.service
 # Enable server to start on boot (user)
 systemctl --user enable auracast-server.service
 
-# Restart both
+# Restart all
+sudo systemctl restart dep.service
+
 sudo systemctl restart auracast-frontend.service
 systemctl --user restart auracast-server.service
 
 #print status
+sudo systemctl status dep.service --no-pager
 sudo systemctl status auracast-frontend.service --no-pager
 systemctl --user status auracast-server.service --no-pager