Hey, Buzz!
Does the problem occur with another amp? Have you tried plugging in to another outlet in the house? Does it happen when you move the volume knob?
If it doesn't do it wiht another amp, of course, the problem is in your amp. Try using a grounded circuit. Put in a 3 prong adapter plug & try reversing the 2 prongs in your receptacle. Might work. If it happens when you move the knob, the pot is dirty & just turn off your amp & work that knob all on, thn off, then on & keep doing that for about a minute. Turn it back on low volume & try turning it up again to see if the noise is gone. Another thing to try that's a little more expensive is to buy an inline ground filter to plug your amp in to. They're 50 or 60 buck in Musician's Friend.
Good luck!
Will
Will Burleigh, June 2007