I morphed the gain level and the bass and treble knobs. Control the morph with expression pedal (moog EP-3) into my Voodoo GC. If I move the pedal quickly there is no issue, no lag. If I move the pedal slowly and stop half way and then continue, the sound lags behind the pedal position.
I will ill try the pedal directly into the Kemper to see if it does the same thing.
Do you have another pedal to try?