I didn't really know where else to put this so I figured this was a good a place as any

I've got two MFW's with first gen amps that have worked perfectly for probably 3-4 years I'm guessing. I got them brand new A stock. Last night one of them started buzzing. I turned it off and it stopped and it was late so I didn't bother researching the problem. I just got a chance and tried unhooking the RCA and it still buzzed. I then removed it from the power strip it was plugged into and plugged it straight into the wall, still buzzing. Unplugged the RCA while it was directly plugged into the wall, still buzzed. For grins I plugged it into a ground lift plug and straight into the wall, still buzzed and removed the RCA and still a buzz.
Basically I'm assuming I've now got a dead amp correct? It is still producing sound when turned on but there is that constant buzzing. It isn't crazy loud but loud enough where I might turn into a crazy person if I kept it on.
Thoughts? Possibly some bad capacitors that could be replaced?
Thanks!
Scott