I have a Silent Partner e.Stringer and have been experiencing some tensioning issues. When I strung my first racket on the machine (60 lbs.), I noticed that it felt quite a bit looser than what 60 lbs. normally feels like. So I bought a tension calibrator and soon realized that it was ~15 lbs. off. Since then, I check the tension before I string each racket and each time the calibrator shows different tensions. I was wondering if this is the nature of rotational gripper electronic stringing machines or if the tensioner of my stinger is defective. I would appreciate any help.