Machine momentarily halts on each cut pass?

[Neale]

Not had a repeat of the halting Gerry but I have noticed that between running files if I jog away to change tools and re-zero that can generate an error where half way through a 10min roughing job will suddenly make one axis move about 50% outside the job perimeter and continue.
I think this happens specifically on a job where I have to re-zero it more than once on the same job to the same coordinated. Most strange! I've not had cpu usage up and running when this happened but can do incase it identifies anything.

Are you using an external motion controller? Mach3? Which version? I ask because there are some known problems with at least the CSMIO controllers and certain versions of Mach3 that can give some funny problems like this.