Index: /trunk/src/VBox/Devices/Audio/DrvAudio.cpp
===================================================================
--- /trunk/src/VBox/Devices/Audio/DrvAudio.cpp	(revision 73683)
+++ /trunk/src/VBox/Devices/Audio/DrvAudio.cpp	(revision 73684)
@@ -3053,4 +3053,12 @@
                  pStream->szName, DrvAudioHlpFramesToMilli(pCfgAcq->Backend.cfPreBuf, &pCfgAcq->Props), pCfgAcq->Backend.cfPreBuf));
     }
+
+    /* Sanity for detecting buggy backends. */
+    AssertMsgReturn(pCfgAcq->Backend.cfPeriod < pCfgAcq->Backend.cfBufferSize,
+                    ("Acquired period size must be smaller than buffer size\n"),
+                    VERR_INVALID_PARAMETER);
+    AssertMsgReturn(pCfgAcq->Backend.cfPreBuf < pCfgAcq->Backend.cfBufferSize,
+                    ("Acquired pre-buffering size must be smaller than buffer size -- this otherwise will lead to buffer overruns\n"),
+                    VERR_INVALID_PARAMETER);
 
     pStream->fStatus |= PDMAUDIOSTREAMSTS_FLAG_INITIALIZED;