Idk WTF it is, but I'm on my
2nd Majesty that breaks high e strings with too much regularity for it to be my fault.
My Enchanted Forest did it when new, and someone on the Fractal forum told me about abrasive cord, which after a few tries, fixed the problem, which I assume was a burr. Lately it's been happening on my Blue Honu. Same deal.
And my cat, for some strange reason, comes running when he hears the string snap, and wants to play with it. I suppose the first time he was close by, he saw the light reflecting off the loose string, and it caught his eye.
So now he associates that sound with it.