Epson Surecolor P600 - Printing on Vellum?

I replaced my R3000 with the P600 and when I try to print on vellum (something done without any problems with the R3000) the paper jams. The paper appears to load without a problem, but before printing it indicates that there is a paper jam and tells me to gently remove the paper. Is there any way I can alter some setting somewhere that will allow the paper to load and print? Thanks - george