I would suspect two things.
1). the potentiometer (aka, the volume control) is defective. I can be replaced (desoldre, resolder, some mechanical ingenuity to get it out and back in again). The part will be (most likley) marked with its value and perhaps even a part number.
2) you may have a leaking capacitor in your gain control circuit, though I would suspect the two channels wouldn't behave quite the same. You don't say. This will require a schematic and a knowledgable tech (or lots of poking around time). Cost to replace the part(s) will be trivial and the time to do so won't be much more. But finding the darn thing isn't going to be easy, unless the capacitor has failed in some visually or smell detectible way. Schematics can be found from Sams Photofacts, from asosrted sites on the Web, ... Cost will be less than replacing the unit at least for schematicatc/manual, parts, time to remore and replace, but may not be for the time needed to find the fault.
will, August 2006
