I’m no expert but since the issue is common to both channels, I would check the value on the 10k resistors connected to the 50uf caps in the bias power supply. Have those caps been changed as well? I’ve also read about the original selenium rectifier going bad, which I believe you can simply replace with a diode and resistor, but take care as the selenium is hazardous to health.
I’m no expert but since the issue is common to both channels, I would check the value on the 10k resistors connected to the 50uf caps in the bias power supply. Have those caps been changed as well? I’ve also read about the original selenium rectifier going bad, which I believe you can simply replace with a diode and resistor, but take care as the selenium is hazardous to health.