Not sure which forum this belongs in (maybe tweaks/connections?), so I thought I'd share my experience today: I live in Tempe, AZ, and today I had Cox come out and install digital cable. The moment the cable was hooked into the wall, hummmmmmmmmmmmmmmmmm. 'Dangit' I think to myself, ground loop problem. The first thing that pops in my head is, I can just run a wire from the ground terminal in my surge protector (the surge protector that my Amp is connected to) to the outer conductor of the cable coax. This majorly reduced the hum, but it was still present. So I decided to trek over to Rat Shack and buy these two parts: http://www.dplay.com/tutorial/cablehum.html I hook them up to the wall. The hum is completely gone! That is, until I put my ear up to my speakers...It's still there. So I figure, why not try using my first idea in conjunction with the Rat Shack parts. Bingo! The hum is completely gone. Fine print: There are 'ghost' images on some of the channels. I'm now off to figure out how to get rid of those. If any of you have some ideas on how to get rid of them, by all means, please share them.