WF 7010 paper does not exit the duplexer

I have a Epson WorkForce WF-7010 Wide Format printer. When printing on both sides of the paper using Letter sized paper, the paper will not exit the duplexer to print the reverse side.

This fails about four out of five times.

It is not a mechanical jam, as I do not have to physically clear the paper. I just push the eject button on the front panel and the paper is ejected with only one side printed.

I've removed and inspected the duplexer, and it seems to be fine.

I've put in "new" paper from an unopened pack, but it makes no difference.

I do hear a ratcheting sound when the printer tries to flip the paper, as if it cannot grasp the paper. The printer is less than three years old.