MuteCurrentProcess.cpp

// Requires Windows 7 or later
_COM_SMARTPTR_TYPEDEF(IAudioSessionManager2, __uuidof(IAudioSessionManager2));

bool MuteCurrentProcess() {
    IAudioSessionManager2Ptr mgr;
    CreateSessionManager(&mgr);
    ISimpleAudioVolumePtr volume;
    if (SUCCEEDED(mgr->GetSimpleAudioVolume(&GUID_NULL, false, &volume))) {
        ISimpleAudioVolumePtr vol;
        volume->QueryInterface(__uuidof(IAudioEndpointVolume), (void**)&vol);

        if (SUCCEEDED(volume->SetMute(TRUE, 0))) {
            return true;
        }
    }
    return true;
}