Hi - I have a carver 2000 receiver, has static on one channel, doesn't vary based on volume. Hear it thru speakers and headphones with volume all the way off. I heard on other carver models this may be 4 transistors - does anyone know if it is the same 4 transistors in the carver 2000, and should I replace them with the same transistors in the service manual, or are there different spec'd transistors that work better - any help greatly appreciated.