It's happened now in Tony Hawk Project 8 and Condemned 2. I think it's a system bug that has something to do with 2.41, the 80G PSP, or the dual shock or some combination thereof. It seems to happen either when the dual shock is running low on batteries or when the dual shock is plugged in to the USB cable, I'm not 100% sure. After that point, the L2 and R2 buttons completely stop responding in disc-based games. Exiting the game, restarting, switching games, switching controllers, or turning on/off the controller does nothing, the only way to fix it is by turning off the system. Strangely, if I start an HD-based game, namely Tekken Online, the L2/R2 respond fine, however if I restart the disc-based game afterwards they continue to refuse to respond. Really weird, huh? I've only noticed this bug since I installed firmware 2.41.