Well... bad news. My first practice since acquiring the amp, and it takes a colossal dump in the middle of the first song. The volume just drops to near nothing, and if you turn the volume knob back a forth a bit, it would kick back on for short bursts of time. Is this possibly a bad preamp tube? The power tubes appeared to be glowing normally, and showed no sign of trouble. It didn't feel like it was emanating too much heat, the back cage was warm to the touch and the fan ran,silently at that. Anybody have this problem before? I only played it for a few minutes in the store... and at practice I let it warm up for at least a solid 1/2 hour before I played it. I don't think I had the volume higher then 3 or 4, so I don't think I was pushing the amp all that hard. I'll probably end out taking it back where I got it from and see about them fixin' it, unless someone here already knows what to do.