Not sure about the string breakage,possibly nicked string, but FYI I clean clamps, tensioner, clamp shafts, cam surface & the rails where the clamps glide before each session & the clamping surfaces after every 5 or 6 racquets. The clean clamps allow me to use minimal clamping pressure. I use a Star 4 machine.
I just think that things should work the way I expect them to.
Pure Storm GT primarily