My wife has a Nuwai 2xCR123 LED flashlight in her purse that I bought for her a few years ago from a fellow CPF'er. It was modded before I got it so I don't know what kind of LED is in it. It (was) very bright and it had a very smooth beam with no dark spots while white wall hunting. It had a nice round, white beam. A few days ago she told me it had stopped working and I proceeded to change the batteries. When I put in new cells and tried it out the beam is no longer white and round. The beam is rainbow colored and it's shaped like a rainbow, several rainbows actually. The LED looks normal with no damage that I can see. She said it hasn't been dropped. The colors are very pretty but the light is no longer what I'd call a good flashlight. The brightness is maybe 25% of what is was before. Any idea what happened? I've never seen anything like it before.