Dot Matrix Printer & form size

We are using a high speed printer which uses an Epson emulation. The size of the form is 8x5. Before we switched to Windows XP (came from 98) the form size printed fine. Now it keeps jumping up by a quarter inch with each ticket. So that by the third ticket the printing is too high on the form. Any ideas on how to fix this? I have played around with the print drivers & the only one that works (doesn't print jibberish) is the Espons FX-100.

Thanks,
Kate