Weds night, 10:40 PM Update;

Everything is unplugged from the Denon. I have the Denon and 7700 connected using RCA cables, and both are plugged into a monsterpower 2600.

I unplugged the monster powerbar 1100 that supplies the Sony 60" SXBR TV and 250 watt Def Tech Sub.

I would say 99% of the hum/buzz is gone. If I put my ear directly in front of the horn tweeters on my Klipsch RF7s, I can just barely hear a very very quiet buzz. This is tolerable.

Now I am about to start hhoking things up.

UPDATE 11:25 PM

I think I found the problem. I had a component video cable with analogue audio for a Sony PS2 that when I plugged in the left and right audio portion, the hum got louder.

I am still plugging items in, but I have the TV and sub on, and still only a very very faint buzz is still audible. If I am within about 3 feet of the speakers (left, right & centre) I can hear it, barely. I cannot hear it from the surrounds (Klipsch RS7s hanging high near the ceiling) unless I climb a chair and get within a foot of them.