IMMDeviceEnumeratorVtable.GetDefaultAudioEndpoint

Undocumented in source but is binding to Windows. You might be able to learn more by searching the web for its name.
struct IMMDeviceEnumeratorVtable
extern (Windows) @nogc nothrow
HRESULT function(This_, EDataFlow dataFlow, ERole role, IMMDevice** ppEndpoint) GetDefaultAudioEndpoint;

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