It looks for me you have some sort of Laser Driver Module problem. You told us first job/plate looks good. May be after warming up of Accuset you have incorrect laser modulation. Please check coaxial RF cable connectors for good contact
My post above was a little brief as well. Not only chips replacement, but reprogramming the board because one of chips is soldered on-board.
I want to know the problem of Avantra forcing you to purchase new DEC board.