I am in the process of re-capping and replacing bad transistors on this excellent unit. I have been playing it for about a month, but had noticed some static on the rear channels. So decided to get the 2SA726's out of the power amp boards as well as the 2SC1451's. Completed the two power amp boards, but static was still present. Decided to continue on the the power supply board. Recapped that and replaced Q6: 2SA720 with KSA1013YTA. Static issue was still there. Voltage measurements on pin 5 of the power amp boards would not go below about 0.5V and was quite variable, causing the static. Measured the power inputs to the board, and found B1 and B2 were a bit variable. I was warming it up this afternoon to make more measurements. When I came back to it after about 20 minutes, it was in protection. After several measurements found that pin 6 was reading 3V (should be 13.5V) and pin 8 (+B3) was reading 2.4V (should be 30V!). Both were quite variable. Power on that circuit comes from pins 4 (37.9VAC) and 5 (38VAC). There are four transistors on that circuit: Q1:2SD313P, Q2:2SC1318, Q3:2SC945, Q4:2SD313P. Emitter of Q4 feeds pin 6. Emitter of Q1 feeds pin 8. Any thoughts on what might have failed here? What should I test?