Cockpit and Instrument Brightness with XTouch Mini

I'm using the famous XTouch Mini MIDI Device with Axis and Ohs, especially with the FBW A320. Everything works fine so far, but when I try to assign the rotary knobs in the Cockpit (PFD Brightness, internal Lights) to an Encoder of the XTouch Mini, the Knob in the Cockpit is turning much too slow when I turn the Encoder on my Device. I've already assigned the same Functionality (like PFD left Brightness INC) to Key Down Events as well as Key up Events of the Encoder, I've set the "Roll" Values in both Assignements to 9, but with no noticeable Effect. The Knob in the Cockpit still turns much slower as when I use the Mousewheel to turn the Knobs. Any Suggestions on how to speed up the Turning of these Knobs?