Drive was removed and connected to PC, and it opened and closed just fince indicating no burner problem. I took this opportunity to cross flash to Sony DW-G120A (aka DRU-120C) to gain normal fast forward function since it was so easy to do after I already had it connected to PC. Replacing the burner in the recorder I discovered it wanted to install a little too far left, and I had to push it toward the right while tightening screws for the bracket that holds the drive in place. It now opens and closes okay in the recorder, and I can only guess it must have shifted to the left after first install which was causing it to touch and thus bind on left side causing difficult opening. Thanks to DR. PAUL for the suggestion, and I’m very glad it wasn’t a burner problem.