This is an annoying problem that I faced the minute I have tried win7 last year.
After a couple of months searching around and finding many other audiophiles sharing the same, I finally went back to win XP.
At that time I wasn't aware of this MC forum. Yesterday I was forced to go back to win7 because my usual dedicated PC was gone for repair. The same glitches and sparks are back when I run win explorer or any web pages, finally could be anything else while listening to music.
I don't know if that issue was treated here? No found.
Is that problem occurred to someone over here and have you found the source?
I won't keep this setup too long. My XP PC is coming back today, but maybe win7 is better for the oncoming upgrades.