Hello all
constant jam out of tray 3 running 11x17 two sided
I have cleaned every roller, clutch and sensors including swapping all the same and no luck
I removed the vertical conveyance door cover so I could watch it and it takes the first three sheets with the fourth sheet stopped at the middle sensor waiting for the first three to duplex then when it's time for the next sheet to go it kicks the code

it runs single sided with no problems

any ideas where to go next? thanks