I recently bought an HP Desjet 722C printer from Ebay (don't even say it!) and it will not pick up paper properly. It only works is the paper tray is totally full. If it is not the printer will not grab a piece of paper until the second try, and even then it will put a small fold in the paper where the roller grabs it. Is there any way I can fix this? What could be broken? Everything looks like it is working properly. Thanks for any help.