Originally Posted By: androidus
The three footswitches can also be assigned to various functions, bearing in mind that the Exp (expression) is designed for continuous footpedals, and the Sustain and FS2 are for momentary footswitches.


Yeah, that right there tells me the regular sustain jack can only handle on/off sustain pedals. Try it in the expression plug and see if it can be reassigned, or at the very least you can look at the MIDI monitor to see if the pedal can at least transmit a variable signal through that jack.

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