I am having a repeated problem with my G23 with M3 light attached. When brand new, the m3 stays on well while firing at the range, however it seems like as time goes on, the light starts to fall off. I am now at the point where the light falls off after firing 2-3 rounds. I have spoken to both Glock and Insight Technologies, the maker of the m3. Insight has replaced this light 3 times, but I eventually end up with the same problem. They promised to test fire my light on one of theri G23's, but did not and just replaces it instead. Glock says to buy a Glock light. Insight says that the M3 was specifically designed FOR Glock before they decided to make their own light. Both companies deny having heard of any widespread problem, but I have seen this problem occur with other guys also, mostly firing the G23, but also with the full sized G22. Has anyone else encountered this problem and does anyone have a solution (besides "buy a new light") ?