Still puzzled about finding the cause of the variable oscillation in the Audio board after recapping electrolytics. Low/high tap gets faster with more volume or more bass after unit is warm, no noise when cold. I'll be changing the bias trimmers to multi-turns, and I wonder if changing the transistors Qm7, Qm8 would help. Bias fluctuates pretty high when the amp heats up, then the drumbeat sounds. Please help, it's beyond me! I guess it gives me a new opportunity to learn, right? Thanks so much!