Kenwood KA-6100: Diagnose and Repair Bad Channel

I had previously repaired this amp about a year prior where it had a bad output pre-driver transistor and burned resistor in the push-pull amplifier. In doing so I inadvertently used too much heat transfer grease when re-installing the final output transistors which were removed for testing. Unit played months trouble free and sounding great. Little did I know that excess grease would become a ticking time bomb and create an interesting troubleshooting scenario. Enjoy.