My Porter Cable Da suddenly has trouble starting. If you flip the switch a few times or bang the side of the polisher it will sometimes come on. It's a couple years old and has been used professionally but I think it should definitely have some use left in it.

Has anybody experienced this. I'll probably go buy another one, because I have a big corvette paint correction this weekend, and then take this one apart to see what is going on. I need a backup anyway. Hopefully once I get it apart it will be something obvious.

Bad switch? Loose connection? Any suggestions?