A while ago I was suffering from a choppy audio problem in Windows 7 which affected all audio, no matter which application it was played from. CPU load was fairly low and putting audio apps like Winamp in top CPU priority didn't help.
By complete accident I came across software that inspected all the running applications and drivers and determined whether the system was fit to play continuous audio, and if not, what the cause for the problem was. At that time, the culprit was a network driver installed by a packet sniffer.
Now I am experiencing the same problem again (don't have any packet sniffers), but forgot the name of the application I was using. Does anyone know about such a thing?