Footswitch problem on SC212

[holden]

I have a Teal stripe Stereo Chorus 212 with the four button footswitch with LEDs. The only button on the footswitch that doesn't work is the Clean/Bypass button. It worked a few times when I first tried the switch, but stopped working.

I have the channel select button on the amp in, so it's not that. The Reverb, Chorus and Lead/Crunch buttons work. All the LEDs work, including the Clean/Bypass on (in other words, toggling the Clean/Bypass button also toggles the LED on and off).

I took the bottom of the footswitch off and verified all the switches work and the cable plug pins have continuity with their switch-end wires. I de-oxyd the plug and socket.

I sometimes hear a clicking in the amp when I hit the Clean/Bypass switch and wonder if there is a little solenoid or relay in the amp that has gone bad that is controlled by the switch?

TIA.

[Jazz P Bass]

Peavey Stereo Chorus 212 Schematic

Here is the schematic.
Yes, there is a relay, among other items in the switching circuit.