i did that and nothing happened. The weird thing is that there is NO hum or hiss in the surrounds which are also connected to the system. I am not blaming the 7500 (the 2200's power the surrounds) but you would think that the ground loop problem would be heard in the surrounds as well. As for the outlets and what is connected to what I have a BIG Monster Surge Protector and line conditioner. That is plugged into a regular 15 amp outlet. These are connected to this Monster powerstrip: LCD TV, cable box, DVD player, both 2200's (using the two "high current" plugs on the power surge protector). Also the SVS sub is NOT connected to the surge protector but it share the same circuit with it. The 7500 amp runs on its own 20 amp outlet that I installed (yes, I did a good job with the right guage wire) but the computer's PSU is also run off of this 20 amp outlet (even with the computer off the hiss is present). It may be important to note that from the 20 amp to the component rack, it has quite a ways to travel . . . on a cable unfortunately designed for 15 amps. I will try to provide a picture later.