Slight hum in my amp. Is this normal?


I have an Anthem A5 and when I turn it on there is a slight "hum" if you put your ear close to it. From 3 feet away it’s unnoticeable. It's in the amp, not in the speakers.
Is this normal?
oldschool1
Use a balanced power source and it'll go away.  A Furman, Euqitec, Tourous etc.  


Good Listening

Peter
Post removed 
I bought a now discontinued PS Audio Humbuster III to solve that issue and it did. Those things show up for sale here and there and something like that should be made by somebody else, but I’m not sure if that exists. Maybe as part of a good power conditioner.
I don’t recall ever hearing it before. When I moved into a new home, the right surround was dead. I took it to an authorized Anthem service center, the only one in the USA, they couldn’t find any problem so as a preventative measure, they disassembled it and reseated everything. When I powered it up is when I noticed. Note this home was built in 1941 and still has "knob and wire" electrical. It looks like everything is grounded but electrical is not my specialty. I’m purchasing a Torus TOT MAX tomorrow so I wonder if that will help. I'm not sure if everything is sharing the same ground. If it were a grounding issue, wouldn't I hear it in the speakers? This is not coming from the speakers, only the amp.
Post removed