[Samples] Error running the samples

[LiorBanai]

Hi,
There is an error when running the netcore CoreAudioForms.Core.Sample
System.IndexOutOfRangeException: 'Index was outside the bounds of the array.'

in:
v = (int)(device.AudioMeterInformation.PeakValues[1] * 100);

[morphx666]

That would indicate that the default audio output is mono (one channel)... what sound card are you using?

I guess the code could be enhanced to check whether the device supports two-channel audio.

[LiorBanai]

I'll check. I also had Invalid cast exception of a device.

[LiorBanai]

Hi @morphx666
the error I'm getting is
System.InvalidCastException: 'Unable to cast COM object of type 'System.__ComObject' to interface type 'CoreAudio.Interfaces.IMMDevice'. This operation failed because the QueryInterface call on the COM component for the interface with IID '{D666063F-1587-4E43-81F1-B948E807363F}' failed due to the following error: No such interface supported (Exception from HRESULT: 0x80004002 (E_NOINTERFACE)).'

the code is

        devEnum = new MMDeviceEnumerator(Guid.Empty);
        defaultDevice = devEnum.GetDefaultAudioEndpoint(DataFlow.Render, Role.Multimedia);
        defaultDevice?.AudioEndpointVolume?.VolumeStepUp(); // here is the exception

[morphx666]

Hi @LiorBanai, I just tested it myself and it worked.

So... what happens if you query the StepInformation of AudioEndpointVolume?

AudioEndpointVolumeStepInformation si = defaultDevice.AudioEndpointVolume.StepInformation;

Also, I think it would be helpful to have some information regarding your setup: Windows version and the sound card brand and model.

[LiorBanai]

sure I'll collect it this week. Thanks for your help.
I think the issue is reproducible if you create the objects on one thread but access it in another
(access defaultDevice?.AudioEndpointVolume?.VolumeStepUp(); in different thread).

[morphx666]

@LiorBanai, accessing the device through a separate thread doesn't seem to have any negative effects.

Actually, the CoreAudioForms.Core.Sample sample works by running a task to update the UI.
But, just to be sure, I added some code to access the VolumeStepUp method and it worked just fine.

[LiorBanai]

The issue is not reproduceble on my end so I'm closing the issue. Thanks for you help