I had a serious ground loop hum that I was able to isolate to the tv cable being the culprit. The only bandaid that worked was if I unplugged the tv cable altogether. I had electronics plugged into a 15 amp non-grounded circuit and others, including the amp, plugged into a 20 amp grounded circuit.
Moving all electronics over to the 20 amp grounded ciruit resolved my problem.
Moving all electronics over to the 20 amp grounded ciruit resolved my problem.