Well I talked to service and they believe it is line noise also. The problem is that my other amps are silent and the noise has just recently become an all of the time issue with the 755. Outlaw thinks that my service is too small for my house and while I agree, nothing has changed in the house to warrant the sudden sensitivity the amp has to the noise. The amp is just over 5 years old and I would have to say it served me well but I am starting to believe it is time to put her down. That was the last Outlaw piece left in my system and I do not want to chance a hum issue again so I will bid all farewell and good luck. My parting words will be that I have always been extremely satisfied with Outlaw's products and service and they are an excellent value for the money. It has been a pleasure!!!