Johnwowen, I have had an almost identical situation. One dedicated outlet for source components plugged into a powerwedge 114 and one other dedicated outlet for stereo amps. Always was very quiet with a wide variety of stereo amps. However, I purchased monoblocks and got a very loud hum when they were either plugged into the same dedicated outlet or into separate outlets. One cheater plug did not work, I had to use two. Also, I have tried out another set of monoamps from a different manufacturer and they did the exact same thing! Quite frustrating! This doesn't happen at my friends house. Yes, all circuits are properly grounded, though not with separate "dedicated grounding". I will be trying balanced interconnects (really my only guess at what might cause this) in a week or so to see if this helps. Otherwise, I'm sticking with the cheater plugs.