Since updating to Mountain Lion (and currently running 10.8.2) I've had this terribly and horribly frustrating issue with the mouse uncontrollably flickering and jumping around the screen, in conjunction with whatever's playing in iTunes jittering. The odd thing is, it only ever happened whenever I was playing a game (which was only ever Diablo 3 or World of Warcraft). Which are very mouse dependant. I stopped playing them eventually, to see if updates would come to Mountain Lion to fix the issue, updates have come and gone since then, and during that time I never really found myself going back to playing those games anyway. Until today, and the issue still remains. I've tried different mouses, i've tried closing all applications including iTunes, but the mouse still flickers and jolts the game during gameplay. I can't for the life of me think what's wrong, other than it being an OS problem. Which I'm now here asking: Does anyone know of a fix?