Use GetMixFormat() instead of PKEY_AudioEngine_DeviceFormat.

See #286 for rationale.

diff --git a/src/hostapi/wasapi/pa_win_wasapi.c b/src/hostapi/wasapi/pa_win_wasapi.c
index 0daa221020d87d08b638507e86f01c929d176f25..7c3a9e9a58025c6a168b8aacd29d63c0aac9a8cc 100644 (file)
--- a/src/hostapi/wasapi/pa_win_wasapi.c
+++ b/src/hostapi/wasapi/pa_win_wasapi.c
@@ -1790,19 +1790,6 @@ static PaError CreateDeviceList(PaWasapiHostApiRepresentation *paWasapi, PaHostA
                                        PA_DEBUG(("WASAPI:%d| name[%s]\n", i, deviceInfo->name));
                 }
 
-                // Default format
-                {
-                    PROPVARIANT value;
-                    PropVariantInit(&value);
-                    hr = IPropertyStore_GetValue(pProperty, &PKEY_AudioEngine_DeviceFormat, &value);
-                                       // We need to set the result to a value otherwise we will return paNoError
-                                       // [IF_FAILED_JUMP(hResult, error);]
-                                       IF_FAILED_INTERNAL_ERROR_JUMP(hr, result, error);
-                                       memcpy(&paWasapi->devInfo[i].DefaultFormat, value.blob.pBlobData, min(sizeof(paWasapi->devInfo[i].DefaultFormat), value.blob.cbSize));
-                    // cleanup
-                    PropVariantClear(&value);
-                }
-
                 // Formfactor
                 {
                     PROPVARIANT value;
@@ -1855,6 +1842,24 @@ static PaError CreateDeviceList(PaWasapiHostApiRepresentation *paWasapi, PaHostA
                                // [IF_FAILED_JUMP(hResult, error);]
                                IF_FAILED_INTERNAL_ERROR_JUMP(hr, result, error);
 
+                               // Get the default format.
+                               //
+                               // Note: this is using IAudioClient::GetMixFormat(), not
+                               // PKEY_AudioEngine_DeviceFormat, because the latter has been shown to
+                               // be unreliable - see:
+                               //   https://app.assembla.com/spaces/portaudio/tickets/286
+                               // The downside of using GetMixFormat() is that the sample type reported
+                               // by PaWasapi_GetDeviceDefaultFormat() will always be 32-bit float.
+                               // That seems fine since PortAudio will automatically do any required
+                               // conversions.
+                               WAVEFORMATEXTENSIBLE *format;
+                               hr = IAudioClient_GetMixFormat(tmpClient, &format);
+                               if (SUCCEEDED(hr))
+                               {
+                                       memcpy(&paWasapi->devInfo[i].DefaultFormat, format, sizeof(*format));
+                                       CoTaskMemFree(format);
+                               }
+
                                // Get latency
                 hr = IAudioClient_GetDevicePeriod(tmpClient,
                     &paWasapi->devInfo[i].DefaultDevicePeriod,