I have a pretty old wacom tablet; a graphire 4 and it seemed to work well but I've encountered a problem where I start using it in photoshop, gimp or MyPaint (or even just hovering the stylus over, I believe.) and suddenly after a while, but most of the time immediately, I can't click anywhere on the screen. nothing responds and that goes for the normal mouse as well.
sometimes I will notice that the hover effects on docks and other stuff are still active and my short-cut keys for my keyboard still work so I know the system is not locked up. I've tried restarting unity and compiz and it fixes the problem for about 5 seconds before the mouse stops working again even without using the tablet. The only solution so far is to reboot and not use the tablet.
This is a really important thing for me so any help would be greatly appreciated.