My guess is that your discs have been beat in and do not have the same flight pattern as when they were new. They have become more understable. You probably also have quite a bit more snap which will cause your discs to turn over and go right. The easiest cure is to release the disc at more of a hyzer angle. The other option is to spend more money on discs. Buy the same discs but in higher quality plastic. If they are already high quality plastic, buy heavier ones. If they are already high quality plastic and max weight, it's time to get more stable/overstable ones. Good luck.