I've got 8 of these things, had them for a few years, never seen this weirdness.

Last time I charged it, it seemed fine until I turned it on. Now it's cycling through every mode; low -> high -> red -> red blinky. It's been doing this for 3 days! Had to shove it in my desk drawer because it's driving me nuts. No, it won't turn off.

Can't find any reference to this behavior. Ideas?