diff --git a/alsaaudio.c b/alsaaudio.c
index b5b8295..5ac7fa8 100644
--- a/alsaaudio.c
+++ b/alsaaudio.c
@@ -1610,7 +1610,7 @@ alsamixer_getvolume(alsamixer_t *self, PyObject *args, PyObject *kw)
     PyObject *result;
     PyObject *item;
 
-    static char *kwlist[] = { "channel", "direction", "unit", NULL };
+    static char *kwlist[] = { "direction", "unit", NULL };
     
     if (!PyArg_ParseTupleAndKeywords(args, kw, "|Oi:getvolume", kwlist, &dirobj, &unit))
         return NULL;
@@ -1646,7 +1646,13 @@ alsamixer_getvolume(alsamixer_t *self, PyObject *args, PyObject *kw)
                                                                   ival));
             }
             else {
-                snd_mixer_selem_get_playback_dB(elem, channel, &ival);
+                int rc = snd_mixer_selem_get_playback_dB(elem, channel, &ival);
+                if (rc < 0) {
+                    PyErr_Format(ALSAAudioError,
+                                 "snd_mixer_selem_get_playback_dB failed: %d",
+                                 rc);
+                    return NULL;
+                }
                 item = PyFloat_FromDouble(ival / 100.0);
             }
             PyList_Append(result, item);
diff --git a/mixertest.py b/mixertest.py
index 92e8353..5636cb9 100755
--- a/mixertest.py
+++ b/mixertest.py
@@ -46,13 +46,17 @@ def show_mixer(name, kwargs):
     print("Capabilities: %s %s" % (' '.join(mixer.volumecap()),
                                    ' '.join(mixer.switchcap())))
     volumes = mixer.getvolume()
-    for i in range(len(volumes)):
-        print("Channel %i volume: %i%%" % (i,volumes[i]))
-        
+    for i, v in enumerate(volumes):
+        print("Channel %i volume: %.02f%%" % (i, v))
+
+    volumes = mixer.getvolume(unit=alsaaudio.dB)
+    for i, v in enumerate(volumes):
+        print("Channel %i volume: %.02fdB" % (i, v))
+
     try:
         mutes = mixer.getmute()
-        for i in range(len(mutes)):
-            if mutes[i]:
+        for i, m in enumerate(mutes):
+            if m:
                 print("Channel %i is muted" % i)
     except alsaaudio.ALSAAudioError:
         # May not support muting
@@ -60,8 +64,8 @@ def show_mixer(name, kwargs):
 
     try:
         recs = mixer.getrec()
-        for i in range(len(recs)):
-            if recs[i]:
+        for i, r in enumerate(recs):
+            if r:
                 print("Channel %i is recording" % i)
     except alsaaudio.ALSAAudioError:
         # May not support recording