I am having issues with the laser not firing during engraving, then starting and going off. The laser has been working correctly has only started having issues today. I have the latest version of lightburn and have also tried the previous version of the software. Same fault with the laser not firing constantly, I have checked all connections and all seem ok.
Just a wild guess, but check the cable at the laser. It seems to malfunction in one area, that could be caused by a broken cable inside the insulation. With your safety glasses on, turn on the laser at low power and wiggle / move the wire harness near the laser head. If the laser goes off and on while wiggling the wires, you have found the problem.