https://learn.microsoft.com/en-us/windows/win32/api/mmdeviceapi/nf-mmdeviceapi-immdeviceenumerator-getdefaultaudioendpoint
IMMDeviceEnumerator::GetDefaultAudioEndpoint (mmdeviceapi.h) - Win32 apps | Microsoft Learn
The GetDefaultAudioEndpoint method retrieves the default audio endpoint for the specified data-flow direction and role.
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