Since I upgraded to mountain lion, my mouse buttons seem to release in the OS, even though I'm holding them down. I've changed the batteries, adjusted the double click speed with no effect, and the problem doesn't happen on RDP to a Windows box. Is there anything else which could cause it.
It's like when I drag (to select or move a window), the selection and moving will start, then stop as though I've released and repressed the mouse button half way through.
