Reply to Limited range of controls for X1

So, I like my X1s. I have them mapped slightly away from the defaults, as I use something else to control effects.

If I set one of the knobs in the effects section to control the mixer's Filter, it sweeps out really fast. Is there a way to make that happen slower; alternatively, is there a way to set the range narrower? I know it's not MIDI, but something like making the knob send 32-98 over it's range instead of 0-128?

Is it just a matter of switching the knob to relative (instead of direct) and playing with the sensitivity, or is there a better way to do it?