Loud humming noise

try plugging into a different socket if that doesnt solve problem you may need to replace cord. sounds like a loose neutral in socket though.

check your audio line in connection, either L or R signal line floating may also cause humming noise. Sub woofer usually very sensitive. If your audio input not connected, do you still hear humming noise? in actual you should not hear such noise, unless volume at max then it is possible to hear little.

TRY TO GOOGLE IT?

I have sort of the same problem...there was a loud snap(kind of electical spark like) then the unit started humming loudly which changes sound as you move the unit around. The picture remains clear and the fan is quiet in shut down mode...still the wheel you think?

yes your right... it could be the wheel bearings, try replacing them.

replaced the light engine. yhis set is probably not cost affective to fix.

Replace the fan motor. Sounds like bearings are going bad.

Not sure yet, but before considering a fault with the amp, does it only make this humming noise when not plugged into the guitar? I am thinking that the cable might be faulty.

If it while the cable is plugged in the guitar, does the humming disappear when you turn the volume control(s) down on the guitar? I am thinking that one or pickups may be faulty.

First,
Disconnect any input cables from the amp. Turn down the volume controls and disconnect the speakers. Power back on. If you still blow fuses with nothing hooked up, have the amp fixed.
If the fuse holds, shut down and connect the speakers, leaving the volume controls down. Power up and see if your fuse holds. If you have hum, an output transistor is most likely shorted. If you have no noise, SLOWLY turn up the volume controls and listen for the hum. If all is quiet, turn down the volume controls and connect your input cables and turn the volume back up. Noise? check your cables!
Mister Phil

on what cd dvd ? cheak cable 1st rca swap out