How to record "What you hear" in Windows Vista
Recently I had a need to record the stereo mix or “What you hear” sound output from Windows Vista. I used to be able to do this in Windows XP without a problem. I prefer Adobe Audition for all my sound/audio mixing, and every time I’ve tried to get this to work since installing Vista several months ago, it just hasn’t worked. I never really put any time into figuring this out until recently. I stubmled upon this link to downloadsquad which had a great blog post with screenshots on how to re-enable the stereo mix channel in Vista. I guess Microsoft decided people didn’t need this feature in Vista and just disabled it by default in Vista on purpose.
Once I followed the instructions in the link above, I was able to configure Audition and Audacity to use the “Stereo Mix” channel and set my input levels. I tested everything out and it works great. One thing I think is a little strange is that the audio levels seem amplified quite a bit, possibly due to the default level for the stereo mix channel being set to 23 (I think). Reducing this to zero may alleviate this, but I found it just as easy to reduce the volume levels in Windows or in the media player being used to get around this.