Fisher K10: Dry Signal on Reverb Only mode

Hello,
I've been noticed that when I'm putting the selector mode in "reverb only" position and disconnecting the reverb tank from the amp unit I can hear from the output jack a dry signal (that I don't want to hear on "reverb only" mode).
If I'm getting it right, the dry signal coming from the plate of V1?
And if I would like to remove the dry signal from the output can I add a coupling capacitor to ground between R5 to R29 and send the dry signal to ground before the output?

There is no spot in the circuit as designed for there to be dry getting through. Those switches are fairly cheap so I would start with cleaning it up first. Next up would be to make sure those filter caps are upto snuff, though I doubt the dry signal is sneaking in there.  If you want to be sure there is no dry signal clip the end of the 470k resistor that feeds the switch to ground.