I have had no problems with the 7125. I have just installed the 7700 and upon turning it on I noticed loud humming through my speakers while it "clicks" 3 times internally to completely turn on. I understand ground looping may be the culprit, due to the 7700 having a 3 pronged plug vs. the 7125 having only 2. I have done the following to remedy the problem: A dedicaded 20 amp breaker, just for my home theater (I should have done this while I used the 7125 anyway). I used a separate, isolated ground wire for this outlet itself. Checking the system at this point made it 50% better, but still not acceptable. I have disconnected the cable TV feed from its source, just to see if that may help, but no change. I am running very good shielded interconnects, and run my power cords away from any other wires. I have been trying everything and anything to eliminate "noise" from the electric in my home, including removing all 5 dimmer switches in the house, which did not help. The last thing I have tried was temporarily running the system without a ground at all, which helped tremendously. I can still hear a faint humming, and after leaving it on for about 10 minutes, it completely disappears.?.
And when I turn the 7700 off, after about 5 or 6 seconds, I will hear a cat "meow" through all my speakers. Is this normal? Is the clicking normal? Again with no problems with the 7125, what's the deal? Anyone with any thoughts on this would be greatly appreciated. I will keep all updated!