I've been having a weird problem in the last two or so months where sometimes (it can be in almost any application, and happens seemingly completely randomly, with no repeatability) my keyboard on my MBP (late 2009) acts as if a key is stuck (normally one of the arrow keys) and repeats it for about 15 seconds before giving me back control. None of my keys feel remotely sticky, and I keep my mac pretty clean, so does anyone have any idea as to what may be wrong?