Getting raw pcm audio buffer from XAudio2 when playing compressed file

Question

Is this possible to access the raw audio PCM data that is being played when using XAudio2 to play file?

I've been searching for several ways to access a decoded version of audio files being played in SL4/Windows Phone, without success.

Answer 1

According to this post someone had success writing a custom XAPO that just grabs samples and is enabled on a Submix Voice. http://social.msdn.microsoft.com/Forums/windowsapps/en-US/05593fad-dfd8-4c77-983b-8c84cd4a324b/xaudio2-saving-output-custom-xapos-slow-down-audio-play-backwards

Please note that if you just want to do this for audio processing this approach is not optimal because you are limited to the speed of audio playback.