Stutter on x xis

Have a strange stutter on x axis. Doesn’t seem to be impacting the finished carve but quite strange. I quite literally just tuned the machine up, new wasteboard, reset all the eccentrics, checked pulley set screws, new belt on x axis.

Belt seems to be tensioned fine, had a bit of stretch after the first couple pieces but has been tightened up now and seems fine.

Unsure what could be causing this. When I open machine inspector and watch the G code there is nothing to suggested that this is a weird bit of code.

Has a weird little pause will moving along x-axis in different spot in each direction.

Any thoughts?