this could still be an issue- not the coffee, but the non-standardness of expression pedals. This is a Roland EV-5.. I now have control over the LFO rate via pedal, BUT, it's erratic. To complicate matters, the pedal pot is connected to yet another pot that attenuates the range of the pedal. I'm confused by what I see inside this thing.
Symptomatically, the largest sweep range brings the pedal into some pop-snap no-sound-at-all territory with the pedal rocked all the way back, then goes slow to fast, faster and then...SLOWER again!
I tried a "peep" photocell passive controller thing and, it's cool but doesn't get it very slow...the variable resistance may not be equivalent to 10K. But that's a start.
Will keep prodding at this...