so i have an AG 602 drop weight stringer. its nearly identical to a gamma progression 602 with flying clamps. my problem is that i seem to get tensions that are way too high. when i string around 55-60lbs it is accurate and feels the same as any other string job. however when i string at 50 or 52lbs there is barely any difference. a racquet done on a different machine is much looser. any ideas why this could be happening?