I picked up an Acurrian ADR 3223 (re-badged Lite-On) last year and the drive has failed, or at least it seems that way.

DVR reported no disc and the tray would not open or close - there was a DVD in it. I took it apart and tried to get it working to no avail. I was able to find a used SOHW-812S and hooked it up. The new drive works in a PC but the DVR still reports no disc, but the tray opens and closes.

Any insight on this? The HDD still functions fine.