So I fire up my 1001RB-II tonight, and a constant high frequency hum starts goin at different pitches until I turn the unit off then it's gone. I turned the power on and off a couple of times and it went away. The hum wasn't like crazy loud but it was definitely coming from the inside of the amp. It seems to happen when the unit is turned off and back on again after a decent amount of playing time. Also I've noticed this amp gets pretty damn hot even when playing at fairly low volumes. I've yet to see the fan spin at even a half decent speed yet. Does it take a lot of heat for it to kick in or what?