@alius2010 It is a mechanical issue called backlash. T2Laser defaults are more aggressive (although still very reasonable), if you disable bi-directional or enable reduced acceleration you will see it goes away. These are band-aids for the real problem, your belts and/or gantry wheels need adjustment.
With smaller jobs and higher detail the carriage (laser head) doesn't have time to catch up with the motors as the belts stretch.