Would you buy a piece of gear with a defect?

If you think you can fix it, yes. I'd offer 50% of what he's asking at the most.

Have you looked inside? JC2 Manual Online (htguide.com) I'm guessing you don't have a schematic. Preamps are usually an easier fix than other components. I read something that this is an FET preamp, if so I'd be concerned about obsolete parts. Do a lot of research! I would offer less than George. Good thing is you have a channel that works, so if it's an open trace on a multilayer board, time and patience could serve you well.

Has anyone noticed that OP has not posted since the original. He must not have truly wanted help or opinions. Maybe this was the seller, not the buyer. Time wasted...

Just checking for a pulse. I do like Parasound a lot, would be a yes for me. I would like to hear about what you find if you pursue.