Since i got my PB used, i have noticed that the left arrow (Home) doesn't work. All the rest of the keys work, but not that one. Then later today i noticed that when i loaded into OS X, the whole keyboard went wonky. It's like the left arrow goes into hyper drive and i can't stop it unless i press the ESC key, then the left arrow doesn't work again. Then in around 5 to 10 min, it does the same thing. From what i gather i may have to replace the keyboard. Has anyone else come across this anomaly before? I have tried an external keyboard, but that does the same thing too. I even tried to reset the pram using option+command+p+r but it just bypasses all of that and boots into OS X.