I just purchased another bowtech constitution. This things is night and day better than the other one that I had. Anyhow, after about 150 shots the nock point moved about 1/4" low. So I moved it up and everything is fine. Except I'm only getting 65% let off at the 80% setting. Any Ideas? The bow is obviously out of "time".How much can you change the string specs before it locks out?