Suddenly my magic mouse won't track properly, can anyone help?

Suddenly my magic mouse won't track around the screen properly, can anyone help? It was working fine then it started sticking. It scrolls from top to bottom fine just the on screen movement is effected. The battery is showing 100%, I've changed the fast/slow slider all the way to the right which has helped a little and unpaired it from bluetooth then re-paired it, did an SMC shut-down, cleaned ball, battery points but it still does not feel totally right? Am I missing something?