- when I give it access to have exclusive control, it works fine, but then I can't hear my computer sounds (like Skype trying to call in) and I can't listen to internet video - unless I have MC turned off. The minute I uncheck the box to allow MC to have exclusive control - MC will play my 24/96 audio files but not my 16/41.
Actually, this a quite accurate description of the WASAPI features as Microsoft designed them to work in Vista and later.
The WASAPI modes bypass resampling, channel coupling and some other DSP features that are built in the Windows audio engine. The Exclusive WASAPI mode is literally exclusive - only the audio stream that uses it can get through. The audio signals from other programs that may try to play audio are blocked.
The "non-exclusive" WASAPI mode allows other programs to play simultaneously, but it still bypasses the processing in the Windows audio engine (it connects to the stream later) and thus the "non-exclusive" WASAPI audio stream must already be in the correct format (= as set in the Windows output options).
The normal mode is DirectSound. It allows the Windows audio engine to process and mix the incoming signals so that the final outputted audio stream is in the format that is set in the Windows audio options.
You can see the WASAPI Exclusive mode as an audio purist's mode. It is useful when the computer is used as a dedicated audio player.
DirectSound is the "computer" mode. It is useful when the user runs various applications that may output audio. The "non-exclusive" WASAPI mode is not very useful because it does not do either of these two things properly.
In general, the quality differences between the output modes are negligible. The distortions that are caused by the signal processing in the Windows mixer are practically below the hearing threshold of the human auditory system. You should choose the output mode according to your intended use.