Index: /trunk/src/VBox/Devices/Audio/DrvAudio.cpp
===================================================================
--- /trunk/src/VBox/Devices/Audio/DrvAudio.cpp	(revision 73575)
+++ /trunk/src/VBox/Devices/Audio/DrvAudio.cpp	(revision 73576)
@@ -1601,5 +1601,5 @@
         uint32_t cbCaptured;
         rc = pThis->pHostDrvAudio->pfnStreamCapture(pThis->pHostDrvAudio, pStream->pvBackend,
-                                                    auBuf, RT_MIN(cbReadable, cbBuf), &cbCaptured);
+                                                    auBuf, RT_MIN(cbReadable, (uint32_t)cbBuf), &cbCaptured);
         if (RT_FAILURE(rc))
         {