Does this issue happen with all your applications like word, excel, adobe? Or is it happening only on one application/file type?
I did find this article in our knowledgebase that may help you do some troubleshooting.
In the Beginning my WorkCentre 6515 used to print correctly when using the Bypass Tray. That means:
According the Symbol on the bypass tray the page was put "face up" in the bypass tray and was also printed on this side.
Suddenly this has changed without me knowingly changing anything.
Now, if i put a page in the bypass tray with the face up the printer will flip the page in the duplex and print on the backside of the page.
Is there any setting to bring the function to original setup? Where?