While it may appear to be the same, it is not. This post is addressing issues with Macs communicating over USB to a Ruida control system. Your setup is different.
When you say you are now using an earlier version of LightBurn, which version? Have you previously been successful using LightBurn with this laser system? What do you mean, exactly, when saying, “sometimes it cut and sometimes not.”? What is the flow or process you are using when you see failure? How are you providing the job, ‘Start’ or ‘Send’?