Sorry if this has been asked before, I did a search but couldn't find the answer

I would like to control my Digitech Whammy WH4 by leaving it in my rack and controlling it with an Expression or Volume pedal plugged into my Rocktron All Access, I know it can be done because Matt Bellamy from Muse has used the same system since 2003

I have an old Bespecko Expression pedal (similar to the Line 6 EX1) for my Line 6 and that doesn't seem compatible with it, I have also got an Ernie Ball Volume Pedal Jr 6180 with a Stereo-Mono Y Lead and that doesn't seem to work properly either. The Ernie Ball is 250k Ohm, the Ernie Ball Matt Bellamy used was 25k Ohm but not sure if this makes a difference

When using one of these pedals, if I have the Whammy on up 1 octave and pick an E note with the pedal back and then push it al the way forward it will go from that E up to about D# so won't go all the way up to the octave, doesn't matter what I do when trying to recalibrate the Whammy

Don't want to keep buying and selling Expression or Volume Pedals until I get it right, any help would be appreciated
Have you tried to find a MIDI Expression pedal (not sure if they even exist) because I remember the WH4 having a MIDI output of some kind. Maybe that will work?
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