Cepheid rate knob suddenly non fuctioning

[GrandRevenant13]

Alright, I built this cepheid chorus for a friend of mine last week, it worked when I tested after building, it worked when he got it home. As I understand, it worked for days. Suddenly, he's at band practice and it doesn't work. LFO not throbbing with the rate, staying steady, but it's still passing signal. He said when he "held the switch down stronger it'd work shortly and the lfo would throb" but as soon as he let go it'd go back to not throbbing and basically no effect.

I have not been able to replicate what he said with the switch. Initially we thought it was a switch issue but now that i have it, the switch is functioning as it should. I checked for continuity in each position and reflowed the joints just incase, no dice.

I toyed with the trim pot again inside, made sure it was in optimal position. The depth knob seems to function, I can hear flange-like sweeps as I turn it. Rate knob and consequently the rate LFO stays constant.

I'd think it's a loose joint somewhere since it was working but I thought I'd post IC voltages with an explanation and see what you guys think before tearing it apart.

Oh! I also reflowed and added a bit more solder to the jump pads you're supposed to bridge depending on the ICs you use; and I got the ICs from cabintech

 

[neiltheseal]

Maybe the pot has stopped working? Measure resistance turning the knob when it is disconnected from power?

If that is no help you could remove the pot and make sure it works.
I have had this happen a few times especially if the pot is under pressure in an enclosure

 

[jwin615]

Could be fastened to tight. I think we've all overtightened the mounting nut at some point. May be able to loosen a quarter turn and it be okay, or the track could be damaged. As neiltheseal said, check with a DMM.