Ok, first the gear:
KPA un-powered toaster (Latest 5.3 beta firmware)
Atomic 112-18w powered cabinet (2 EL84 power tubes and 12AX7 phase inverter)
Behringer FCB1010 Midi Footcontroller.
The problem - Last night at our bands big 10th anniversary gig, about 4-5 songs in, I start getting tone fluctuations. I would describe it as if I was rolling the tone knob on my guitar, to zero, then back up to 10, randomly. This lasted through one song, then seemed to clear up. The next 4-5 songs were uneventful. Then, right in the middle of a slow blues guitar solo (I did dial up the volume here), the sound started cutting in and out randomly, until finally, all I had were the pick attacks, with zero sustain. Sounded like little blips each time I hit a string. Fortunately, I had a 2nd combo amp setup beside my main rig, running parallel as a backup, and it continued working. Eventually, the sound from my KPA returned, and I finished the show with my main rig.
My first thought is that the tubes in the Atomic 112-18 farted out. (BTW, does anyone know if this 18w Atomic 112 cab can bias adjusted? I can only find instructions for the 50w cab). Then I remembered the funky tone stuff early in the show, and thought that maybe it is some kind of midi problem with the new firmware?
BTW, my tone for the whole show was really shrill and high-endy. No amount of tone control adjustment seemed to help. This was definitely not normal.
Any thoughts?