When you " retune" your rest to group your BH and FP, put a mark on the bar that goes through the bracket that attaches it to the bow. That way you will know if your rest is siding on you. I had this prob. with my mirage when I bought it. I would slowly slide to the left. I called GKF and they sent me a different bracket with a set screw to " grab" the bar. It has not moved since.