My pedal isn't broken per se, it's a Yamaha sustain pedal meant for piano but it can be used with the keylab 88 to send a continuous range of CCs and so I want to use it as an expression pedal.
In other words, I'm using it in a way it wasn't designed to be used, so to speak, because I guess on the actual piano, when the player would release the pedal, the piano was engineered so that the pedal didn't have to be sending zero in order for the piano to behave like it was supposed to.
I've already tried opening up the pedal and making some slight modifications to the action but there's very little I can do past a certain point without soldering (I don't know how to solder).
I'm going to try an experiment with studio one macros and the mixer and see if that gives me what I'm after.
In case you're wondering why I'm bothering with this, it's because I've found that it's possible to get really rapid and expressive vibrato when a piano style sustain pedal is used as an expression pedal because unlike a 'wah-style' expression pedal there are different muscle movements involved when your foot is being pushed back against by a fairly heavy spring.