...It also sounds like you may have a ground loop as well. This may be more difficult to diagnose. The key here is to diagnose which connected component is introducing the loop. to make this determination you will need to remove one component at a time from the receiver. Cable boxes are usually a good place to start as a common culprit... I had a WICKED ground loop hum in my setup when I tried to mix a pro amp with a Denon pre-amp. No amount of cable trickery worked, so I had to finally had to pick up a ground isolator. It did the job, and I've been hum free ever since. It's a $20 option worth checking into. Nice finishing job on the speakers, by the way!
