I had mine come off at about 95' on my first dive with a hood. It was leaking much more than normal and I was clearing it much more than usual. One time I cleared it and it came off in my hands. Since I wear contacts when I dive, I immediately closed my eyes and started wondering how I was gonna hold my mask, the anchor line, and control my buoyancy all with only two hands. Then I felt the strap against the back of my hand. Blindly, I put on the mask and cleared it just like I'd been trained to do in OW class. Ironically, that fixed the abnormal leakage.
Come to find out I'd put the strap over the crown of my head instead of totally on the back and didn't notice it due to wearing the hood. I check it now when I use a hood, and it hasn't happened since.