Depends on what kind of hum it is. Is in coming from inside the amp (mechanical / transformer hum)? Or is the hum coming only through the speakers?
Most amplifiers have sufficient filtering internally to overcome potential drivers of hum that might enter through your home's electrical system. While its possible that a power condition might help, it would be the potential cause that I'd investigate last.
Since the amp in question is multi-channel, it seems likely that your system is a home theater, or AV system? If so, is the system connected in any way to cable (maybe via a cable modem and/or cable box)? If so, I'd start there. Does the hum still present if you completely disconnect / isolate your system from the cable box?