Reply to APC 20 - Mapping the cue level knob

I've been trying to map the cue level knob to scroll through songs in my browser, but I can't get it to work correctly. All I can get it to do is scroll between the top and bottom of the list. It will highlight the top track, and once I move the knob a little bit, it will be on the bottom track.

Has anyone else mapped this and have some tips?