Hi! I have been stringing for a few months now using a Gamma Progression 2 crank machine. I also have a string calibrator. I have been mostly setting the tension around the 55lb mark, give or take a few lbs. and every time I finish and check it, the tension registers in the high 60's. I keep checking clibration and it's dead on. Just wondering what I'm doing wrong? This is happening on all types of strings. Is it possible that strings will tighten differently? I have been checking it on an app called "tennis Tension" After setting all the specs of the racket and strings, it reads tension via tapping. It has a 5 star rating, and gives very consistent readouts. I would appreciate any advice or suggestions.