I have a very strange problem with my keyboard. I have a USB keyboard (tried two different keyboards, same problem), and when I type fast it seems to randomly switch into a caplocks mode that automatically clears after a 20 second timeout. When in this mode there is no indication using key-mon (keyboard monitoring program) that capslock is set and you cannot clear the capslock condition except to wait the 20 seconds. Running Gnome over X11, all stock stuff, except that I have the capslock/control swapped option turned on (I've run like this forever, never had an issue).