the only pedal that line6 support is the line6 EX1.  some other pedals do work, but it's pot luck.  if it doesn't work then calibrate it.  if it still doesn't work there's 2 options.  modify the expression pedal or buy another one.

the EX1 has a dual 20K pot inside I believe, with both pots in parallel, so this gives something very similar to a 10K Log pot in the EX1.

Hello,

  As Rowbi mentioned, if the expression pedal you are using does not match the specs of the EX-1 then we cannot guarantee that it will work.

  If there is no way to calibrate the pedal then it sounds like that pedal is not compatible with the X3 Live.

  If all of your questions have been answered please be sure to award Helpful and/or Correct points to community members who respond with helpful or correct answers, and close out the ticket as “answered” if your situation has been resolved. Thanks!

  Lien6Miller

Hello,

  There is no external pedal calibration routine on the POD. You can only calibrate the on board expression pedal.

  Has this answered your question?

  Line6Miller