Month and a half with no answer, awesome! For what it's worth, I've had what i and is the same issue myself. While jogging with theinner MPG wheel it randomly decides to move an inch, instead of my set half thou, in either direction. I've also noticed it occasionally will show an inch change in the DRO output, but actually only moved the .0005 that it was supposed to. At this point the inner wheel is completely useless.