Hello,
Can you be more specific with how you’d like to set this up? Your whole signal chain goes through the input/output of the Mini X, and the aux port of the Mini X would be connected to the H90 exp pedal input? If this is the case, then whenever you adjust the exp pedal setting on the H90, you would also be adjusting the volume of the whole signal chain.
If you just connect the aux port of the Mini X to the H90 exp pedal input, you can map the exp pedal to control the input gain of the H90 and act as a volume swell when necessary, and then map it to other exp pedal functions when you want it to do something else.
