I bought a U2 about a month ago. Fantastic light but I was using it yesterday and it just stopped working and now I can't get it to switch back on. I tried different batteries (didn't change anything) and I can hear something rattling around in the head of the light. I think maybe a capacitor has blown or something. The light was only on for a few minutes at the max and it wasn't knocked around. I've sent an email to Surefire to arrange to have the light returned and repaired. Has anyone had anything like this happen to their U2?