I have a 250ci with service pack 5 firmware and lastest driver version. The problem I am having is the machine and driver are set to single sided. however when printing to drawers 1 or 2 and only when printing the machine runs the paper back through the duplexer. It still only prints on 1 side. When printing from the LCT it does not run it back through the duplexer it functions as it should. I have tried different emulations with no luck aswell as double checked all settings. copy and fax are not affected . any help would be great.

update. the only the setting that was diff from tray 1 & 2 to tray 3 was that tray 3 was set to plain paper and 1, 2 was preprinted I set 1, 2 to plain and it works normally . still would like some sort of answer as to why