Could be, but the Gcode itself is only 10 lines long.
Tweakie.
What I meant was the default lookahead in Mach3 is 20 lines.
What if we change that setting to just 1 (0 is not allowed).
Will Mach3 then execute command line one line at a time SLOWLY?
Should have mentioned this earlier, I have also tried this before, setting the look ahead lines to 1. Unfortunately there is no visible difference in the way it goes.
Today tried to change the NVUM driver but there isn't too much alternative available. I've got 2 DLL's and both of them give the same result. Novusun.dll and Nvum_release.dll.
Also tried to run the g-code with parallel driver loaded. Of course it's not possible to drive the machine, but when g-code running it can be seen the driven coordinate is "vibrating" and sequence seem to be normal. I.e. when the driven coordinate stops "vibrating" then the next command line starts to be loaded and ran.
So far I'd agree with Tweakie, the trouble comes from the NVUM driver. But seems there isn't better way to prove or solve it...