Skytbest

So I currently have a 5.1 setup and its been working well for a while. For some reason in the "sound" menu in the control panel the Digital Audio Interface's (which is set to the default device) default format is set to 2 channels and my speakers (default communication device) is set to 5.1 surround sound. So first of all I'm not even sure if I'm getting true surround sound.

But my bigger problem is that no matter what I set any of these setting to I'm getting a poping noise and then a full on fuzz whenever I'm listening to music in iTunes or any sound (like a video or audio) in Firefox or IE. It seems that no other programs have this problem. Anyone know how I could fix this problem?

Thanks