@g.jie you mean, sometimes when you're going to start swiping, the stuff changes position, sometimes it "snaps" a few pixels down or up? If yes, then that's a bit common on Rockbox - it does not use any scrolling mechanism from maemo, it uses it's own, so I can't do anything. About the issue being more pronounced on this skin, I have no idea - might be just your head or a coincidence.