MS20 Mini volume potentiometer malfunctioning.

[allochthon]

The volume pot on my MS20 Mini suddenly stopped working between sessions. I can manage to get a very low-level signal within a very narrow range at around 2, but is totally dead otherwise, besides still powering the unit on and off. Prior to this, I had been experimenting with feeding the headphone signal back into the ESP, and it seemed to be working fine afterwards.

I opened up the unit to look for loose of bad connections, which I did not observe.

Is this a known issue? I cannot find any reference to it on the internet.

Any help or suggestions are welcome.