I've had some weird experiences with dacron recently...
homemade string, did a good job on it so methinks
shot it for a week every night and used it at the Glamorgan field champs on the 4th, all ok no problems. then all of a sudden the brace height dropped a clean half inch... put so many twists in it it looked braided so had to abandon it. out of curiosity, put it back on a few days later... correct brace height? :s
resorted to a bought string from merlin in the meantime, all cool set the brace height but keeps changing by as much as a cm from start of the shooting night to the end. is bloody weird.