I have a 20W Marshall JCM2000 DSL and recently the clean channel's been acting up. The green LED flickers and the sound dies. I don't think it's a problem with the valves as I don't see why that would affect the LED. The OD channel is fine. Any suggestions?
Sounds like some type of issue with the switching for the clean channel - some sort of power issue. Best you take this into a technician to figure out, unless you know what you're doing inside of a tube amp. Don't even think of poking around inside of it unless you know what to touch and what not to touch.