They have done this pretty much from the beginning, or should I say I don't remember them not doing it. Her last ones which were smaller did it also now that I think about it. I don't remember how much though. Dang, now I'm back to square one.
DD had this problem and solved it by crossing both sets of straps; the uppers and the lowers. The uppers chafed the back of her knee where they crossed so we added a little padding under the straps and she is fine with it. They still turn a little but not nearly as much as they used.
She doesn't like the knee-savers. She thinks they are to bulky. On that note yesterday we bought her a new pair of Easton Mako's 14". The first thing she said when she tried them on is "They feel like they aren't there". They seemed to not want to turn at the store. I ordered them online for $50 less so we'll see how they do when they come in.