I had the same problem til I bought a ground loop isolator. Everything was great til I went with digital cable, then picture quality was terrible. I had a choice, buzz or bad picture. Currently, the ground loop isolator is out of my set-up, my cable runs through my Monster HTS5000 power center and the buzz is not audible to anybody else but me(isn't that always the case). My ultimate solution is this, whenever possible, VHS, DVD, or during CD listening I completely disconnect the cable from my system, again, nobody but myself hears a difference. Actually, the only difference probably is that I know there is no chance for interference. To summarize, you may have to expirement with a few different solutions til you find the one that works for you. BTW - I had the cable company come out and re-wire from the pole and using the same ground as my panel. Until I can afford to have a separate 2ch system and HT system I will always be listening for the ghost of the once present ground loop. Maybe I need a therapist, hehe.
