Ok so this is interesting. I think Ryan may be on to something as far as the acceleration and jerk settings go. Can you create gcode for a small image using both laseretch and image2gcode and post them here? Also post your config.h file. Now that you have lcd hooked up it’ll be much easier to play with accel and jerk settings. They can be changed through lcd interface and the new settings will be written to eeprom. Even under ideal conditions i wouldn’t expect 8bit laser engraving to perform very well at speeds over 1200mm/min or so. The hardware is capable but i doubt the firmware is.