Are you aware, that the functions "Performance Up/Down" assigned to external switches first step and then start to scroll like the Up/Down buttons of the Remote do?
If you want to step jest one Performance Up/Down just step on the switch shortly. And make sure your external switch is momentary. Otherwiese it's hard to avoid scrolling.
Sorry if I'm missing something here Burkhard but I (and I think others) are talking about the up/down buttns on the unit itself. I don't have a remote and yes if I use my midi controller it works fine but I don't need to use the Midi Controller now that I am set up like other right next to my work station. Again sorry if I'm missing your point. Cheers