The amp itself is humming or do you mean to say that it is creating a hum from the loudspeakers? You mentioned disconnecting the cables and IC, but I wasn't sure if you meant that it hums without the cables or that the unit itself is humming with or without cables.

In any event, my first reaction was RF noise from your outlet that could be traveling through your system. That's pretty common. If the unit itself is humming then I would be on the phone with somebody...assuming it's not resonance. Does the hum go away if you put your hand on the chasis?

I'm not familiar with the particular amp so I'll have to beg off at this point. One last thought, are you using ceiling fans in the room? If so, see if the hum goes away with the fan off.

Other than that, you just might have a capacitor going out. Let us know how you resolve this and what the culprit was. Best of luck.

If you are in the United States, perhaps you might want to call MF's US distributor.

http://www.signalpathint.com/

Since you didn't seem to notice this hum for the first several months of use, and since this hum seems to be emanating from somewhere within the chassis of your integrated amplifier (as well as the fact that you now find it to be so noticable as to be annoying), I can't help but wonder if the hum may be coming from a problem that's developed in a toroidal transformer within the amp?

Question: In addition to hearing this hum, do you also feel a corresponding vibration or "buzz" when you place your ear against the top of the amp, or when you lay your hand on it? Also, if you place an ear over top of the amp's outer casing (or alternatively, using just your fingertips), and you then move your ear (or your fingertips) all around the top of the amp (rather like using a stethoscope), where then does the hum/vibration seem to be most noticable? If the hum/buzz seems strongest above where a toroidal transformer resides within the amp, this is information you would definitely want to include in your discussions with the distributor.