mmdevapi: Allow PKEY_AudioEndpoint_PhysicalSpeakers to be overridden.

dlls/mmdevapi/devenum.c

@@ -372,8 +372,18 @@ static MMDevice *MMDevice_Create(WCHAR *name, GUID *id, EDataFlow flow, DWORD st
             }
 
             if (flow != eCapture)
+            {
+                PROPVARIANT pv2;
+
+                PropVariantInit(&pv2);
+
+                /* make read-write by not overwriting if already set */
+                if (FAILED(MMDevice_GetPropValue(id, flow, &PKEY_AudioEndpoint_PhysicalSpeakers, &pv2)) || pv2.vt != VT_UI4)
                     set_driver_prop_value(id, flow, &PKEY_AudioEndpoint_PhysicalSpeakers);
 
+                PropVariantClear(&pv2);
+            }
+
             RegCloseKey(keyprop);
         }
         RegCloseKey(key);