I've only had mine for a couple of days, but I've noticed that when I'm moving a display on the LCD side by dragging with my finger or stylus, when I let go it takes a moment to center itself and come to a stop. Maybe the jump you're seeing is that you're clicking too soon, and the display hasn't gained it's equilibrium yet. What happens if you scroll to where you want to go, then wait a few seconds... then click your selection?
(I understand this wouldn't affect the keyboard strokes.)