NEED HELP - Laser Raster Engraving / Tickle Voltage

Hello,

We have a ULS 50OEM laser that is failing to fire/shut off when commanded, resulting in images with engrave lines that extend past image boundaries in an erratic pattern (some lines extend further past boundary than others). We have solved this gripe previously by adjusting tickle voltage settings via changes to the dip switch configuration.

This time, we attempted the same operation with no result. We also adjusted settings to the maximum and minimum ranges allowable in hopes of some change in symptom manifestation - again with no result.

Anyone have an idea of another component we should investigate, or a certain circuit that could be read to check that we are measuring within parameters? Any advice is appreciated. Thanks