diff --git a/src/python_run/piper/__init__.py b/src/python_run/piper/__init__.py
index 2ab2622..e14d2c9 100644
--- a/src/python_run/piper/__init__.py
+++ b/src/python_run/piper/__init__.py
@@ -1,5 +1,6 @@
 import io
 import json
+import logging
 import wave
 from dataclasses import dataclass
 from pathlib import Path
@@ -9,6 +10,8 @@ import numpy as np
 import onnxruntime
 from espeak_phonemizer import Phonemizer
 
+_LOGGER = logging.getLogger(__name__)
+
 _BOS = "^"
 _EOS = "$"
 _PAD = "_"
@@ -69,8 +72,11 @@ class Piper:
         phoneme_ids: List[int] = []
 
         for phoneme in phonemes:
-            phoneme_ids.extend(self.config.phoneme_id_map[phoneme])
-            phoneme_ids.extend(self.config.phoneme_id_map[_PAD])
+            if phoneme in self.config.phoneme_id_map:
+                phoneme_ids.extend(self.config.phoneme_id_map[phoneme])
+                phoneme_ids.extend(self.config.phoneme_id_map[_PAD])
+            else:
+                _LOGGER.warning("No id for phoneme: %s", phoneme)
 
         phoneme_ids.extend(self.config.phoneme_id_map[_EOS])