I have a CMG Infinity LED flashlight. Some time ago it developed a problem. I would turn it on and it would work for a period of time, sometime very breifly, and then turn itself off. Yet other times it seems to work okay. I've tried new batteries and have cleaned the contacts in the flashlight as well as the battery. I really like this light but with its intermittent operation I can not rely on it. I can not figure this thing out. Has anyone else had similiar problems with LED flashlights?