Last spring my TRRI died. One of the power tubes blew and took out some resistors, I had it repaired, new set of 6L6s and biased then it sat around until last week. I was getting ready to use it again for the 1st time next weekend and it was giving my nasty crackles/hisses when I strummed or took it off of standby, otherwise no weird noise. I also noticed a faint burning smell coming from the amp. It did the same thing with a different guitar and on different channels. I played around with the tubes and when I wiggled the far left tube (looking at amp from behind, I think it's the V10??) the same crackle/hiss noise started. I also noticed at this time that the tube had a faint blue glow and it began to glow much brighter than the other 3 tubes, just like it did last year before it was repaired. I swapped tubes around and it glowed bright and hot in the same position with a different tube. I kept playing around with it, never leaving the amp on long enough to possibly blow a fuse or (hopefully) melt anything important. Suddenly, the amp made a goddawful, screeching feedbacky noise that I couldn't control so I quickly threw it into standby then complete power off. I'm kind of an idiot so I just had to turn it back on and see what was going on after that. I powered it up several times, played, left it on for several hours and put it through live gig conditions and now it acts like nothings wrong. No smell, noises and all tubes glowing the same. It's almost like I exorcised some demon out of it when it screamed and now everything's fine. I'm kinda wary about using this weekend though. Does this make any sense? Do you guys think it's good to go?