HP PSC 1315v printer cartridge cradle jamming - but nothing jamming it?

I've reinstalled and updated all the drivers, cleaned the machine, and checked to be sure there is no paper jammed. It worked correctly at one time, so I know it is not due to packing material. A page will print but at the end, the last part of the paper jams up and I have to physically pull it from the machine. The I get the paper jam errors. Out of options from HP troubleshooting. Any other ideas?