RTAudio reports different capabilities for identical USB hardware on Linux and Windows 10 (ALSA/WASAPI)

[g40]

This is a Windows issue, not RTAudio. This is more a question about mitigation.

When querying a USB interface (chipset is https://www.ti.com/product/PCM2902), GetMixFormat() always reports a 1 channel input device rather the preferred, and available, stereo option.

When enumerating devices and capabilities the WASAPI backend creates an IAudioClient instance and then calls GetMixFormat(): https://github.com/g40/rtaudio/blob/master/RtAudio.cpp#L5164.

Questions:

1. Does the problem with Windows misreporting the channel count prohibit subsequent stereo capture ?
2. Would it be useful to do a more exhaustive probe of the device capabilities? Possibly using IsFormatSupported() and friends.
3. Is there any interest in a patch?

[1] Linux/Mint/ALSA - looks correct.

~/src/audio/loopback$ ./loopback -l
0x00000081 Default ALSA Device In: 64 Out: 64 true true
0x00000082 PulseAudio Sound Server In: 32 Out: 32 false false
0x00000083 HDA Intel PCH (ALC3204 Analog) In: 2 Out: 2 false false
0x00000084 HDA Intel PCH (HDMI 0) In: 0 Out: 8 false false
0x00000085 HDA Intel PCH (HDMI 1) In: 0 Out: 8 false false
0x00000086 HDA Intel PCH (HDMI 2) In: 0 Out: 8 false false
0x00000087 USB Audio CODEC (USB Audio) In: 2 Out: 2 false false

[2] Windows 10 22H2 x64

>loopback -l
0x00000081 Speakers (2- USB Audio CODEC ) In: 0 Out: 2 false false
0x00000086 Microphone (2- USB Audio CODEC ) In: 1 Out: 0 false false