I've not yet tried printing on fabric, but I have argued with printers for years! The faster the print feed the more likely to be problems, hence the previous suggestion to feed one at a time. Also if it is being finicky, running a cleaning cycle can sometimes help. You might even try using cardstock instead of regular weight paper when doing the cleaning cycle to help dislodge whatever is causing the jamming. It can be a tiny scrap of paper or thread that you don't realize is still in there.
Hope you get it figured out!