Volume dial not working on Chmpion 30 DSP

[JWC138]

I recently purchased a used Fender Champion 30 DSP. The Clean Channel volume does nothing and the amp plays at a constant volume that is what I would think "3" or "4" would be if the volume dial were working. Also the Overdrive on the second channel does not work (ie., turn the drive dial and nothing happens . . . the sound stays clean). Any thoughts out there?

[Enzo]

Well, the first thing I'd check would be that control. Cracked solder to it? Cracked control itself? Open element inside it?