Index: /trunk/src/VBox/Devices/Audio/DrvAudio.cpp
===================================================================
--- /trunk/src/VBox/Devices/Audio/DrvAudio.cpp	(revision 65075)
+++ /trunk/src/VBox/Devices/Audio/DrvAudio.cpp	(revision 65076)
@@ -1710,5 +1710,6 @@
 #ifdef VBOX_WITH_AUDIO_ENUM
     int rc2 = drvAudioDevicesEnumerateInternal(pThis, true /* fLog */, NULL /* pDevEnum */);
-    AssertRC(rc2);
+    if (rc2 != VERR_NOT_SUPPORTED) /* Some backends don't implement device enumeration. */
+        AssertRC(rc2);
 
     RT_NOREF(rc2);