Sometimes power supply transformers, especially in amplifiers, buzz. I don't know of anything that will stop it, unless one of those new PS Audio units might. Those might limit current too much for an amplifier, though...
Creek 4240SE has buzzing sound.
I have a Creek 4240SE Int. Amp that is generating a buzzing sound from within the unit (not through the speakers). It is plugged into a line conditioner/surge suppressor (more of a PC type than audio). I turned off everything else in my condo and it was still doing it. Thanks for any help!!!