Odd X behaviour

This isn't an XFCe problem, but I'm hopeing someone can offer some assistance. I'm running SuSE 7.1 with XFree86 4.1.0, with XFCe (it does't matter which version. same on all). After a while, my keyboard stops working properly. In Java applications - most of what I run - a click is seen as a double click. In xgalaga (ya, ya, but a person needs some R&R ;-} ) the keyboard will not control the game. Hitting the 'k' key starts the game, but no further key click is acted on. Restarting XFCe makes everything normal for a while longer. Any ideas?