OK, this has been driving me nuts for 6 months. I really need to fix this. I have a 2012 MBP with an Apple Bluetooth Magic Mouse. I am having intermittent mouse "jitters" - the mouse will become unresponsive for a second or three, or you will have to move it several times to get it to go where you want it to. Best description is that it jitters. I have tried a different, brand new mouse and had the same problem, and this mouse works fine at work. Sometimes a reboot will fix it. It SEEMS to be most correlated with high CPU usage. But my MBP Retina at work with the same type of mouse never has this problem. What can I do to fix this?