I was given a dsl100 issue 5 from 2002 that did not work. All I was told is that it had a bias problem. I bought the stable bias mod and installed it. This involved drilling out pin 5 and bypassing the bias circuit. I've replaced c38 and c39 because they were domed. also replaced c-46 with a 1kv variant because I have read it can take out the board if it goes bad. When I turn this thing on, it doesn't blow any fuses and you can play it, but I can hear the tubes making all kinds of noise. Popping, etc. I never saw them red plate but I didn't leave it on for more than a few minutes. Also, the moment you take it off of standby there's kind of a popping noise through the speaker and then it fades away. During the few minutes I played it I noticed the volume kept getting louder. The bias pins read about 170 millivolt per side with the trim pots all the way down. it was at this point I replaced r77 with a 15K resistor. I had seen on some random YouTube video it would help get that bias down more. I'm not sure if it made it worse or not. I'm pretty sure all the tubes are good. The amp plays, I just don't dare leave it on for more than a few minutes because the bias and the noises the tubes make. To try and save the power tubes I removed them and have been taking some measurements. Pin 1 0v (to ground) Pin 2 3.65vac (to ground) Pin 3 517v (about 450 with tubes) Pin 4 514v (no tubes) Pin 7 3.68vac (to ground) Pin 8 0v (to ground) My knowledge of how tube amps work is quite limited. I do understand the fundamentals and I am aware of the lethal voltages inside of these amps. Any help would be greatly appreciated, I know there's thousands of threads on these amps but I really couldn't find exactly what I was looking for. Thanks.