Each engraving, regardless of image modes and/or scan speed, my laser head stutters like my smoothieboard is busy filling up its buffer or whatever. few seconds later all is well and scans are smooth. this does not reflect on the outcome. you cannot see any differences between first few lines where the laser head jitters to the rest of the image being engraved. speed is set to 100mms but seen this at any speed.
Where should i start looking for what can cause this?