Check to see if your platform is loose first off. I was chasing everything else and finally figured out the platform was loose. I think it's crazy that they don't Loctite those 2 bolts at the factory. When I got my second 650 and when I set my buddy's new 650 up, I loosened one at a time and Loctited them so we wouldn't have a problem in the future.
ETA...you'll have to pull the shellplate off obviously, but it's wirth it to check to be sure and you might as well do a little PM & cleaning while you're in there.