Quote Originally Posted by Mick
Dude, I'm afraid to even look at a capacitor!

If it comes down to modifying the circuitry the way you describe, then I'll take it to someone like you that knows what an ohm is.
Well thought it might help. On the chance changing a tube could have an effect changing V3 may have an effect. This is used as a cathode follower for the clean signal to the reverb and the output. If its cathode impedance was higher then normal it could cause a problem like this. Hope this helps.