Mattmanimal wrote a review of Princeton Tec Byte Headlamp on January 20, 2012
I experienced the flickering last weekend in 23 degree wind. I doubt it was an overheating issue. My take on it was cold batts (alkaline do well in cold for me) After a rest, by flipping the top Batt I was able to leave it in red mode the rest of the evening after which I cycled the switch and experienced the same dim flicker that would not turn off. All that being said, when it works you can't beat the light for the weight. I hiked out at night in red mode. if the bug gets worked out i feel it is a superior product.