PIXMA MX922 keeps jamming paper

[dogla]

Recently my printer is refusing to print because it's jamming paper constantly. Whenever I try to print it will pickup paper and curl it up in the rear duplex slot. Not sure why it's doing that but I've removed the duplex panels to see if there is any debris but it's clean as a whistle. I just repaired this printer (needed a new printhead) and now this....

[DerrickL]

What does the inside top look like, it looks to me like the paper is jamming up near the print head carriage not in the back behind the panels, in other words it is not feeding up where it needs to go. Maybe a roller is jammed or out of position?

https://youtu.be/EI63iQmJza4

[dogla]

I will have a look when I'm back home. Probably will have to dismantle it like in the attached clip. Thanks for the reply, will update after I tried it.