Just talked to SVS, and have determined its a amp issue. Emailed them with the serial #, then they will reply back with the procedure for replacement. He said they are out of the BASH amps, that is the same as the original amp, which is what they use for warranty swaps. Should be about 10 days or so. Said it should be ok to use till then. He mentioned the ground loop issue, but when I mentioned it did it with or without sub cable plugged in or unplugged, he determined it to be the amp.