You can install Mach3 on the same computer and it will co-exist with Mach2. Then you can run either, but not at the same time. Mach3 does not share on import any settings you currently have in Mach2, so you will need to configure Mach3 before using it - ports & pins, etc. Mach3 is more stable than Mach2, but I've never heard of Mach2 doing what you are describing.
You should be able to monitor Mach2 on the diagnostics screen and see if the spindle output is triggering on/off during operation - in you don't see it, then the problem is not with the Mach software.
Are you switching your spindle motor directly with one of the relays on the Sound Logic breakout board? What is the current draw of your spindle motor? Make sure it is not higher that the relay rating - probably 10A. I'm not sure, but perhaps the breakout board has an LED showing status of the relay. Look and see if the relay is pulsing when the problem occurs.
--Colin-- |