We have a (Kyocera FS-2020DN) printer which has two paper trays, one for plain and one for headed. We have hit the problem that when the plain paper tray is empty, the printer automatically goes looking for an alternative source and finds the headed paper. This means that print runs are coming out partly on plain and partly on headed, which is proving both annoying and expensive. Does anyone know of a way of stopping the printer from doing this?

I've already tried changing the source from "auto" to "Cassette 1", but it still goes hunting if cassette 1 is empty. From what I can find on Kyocera's web site, it is because both trays allegedly contain the same type of paper, but I can't see a way of changing the media type for one specific tray.

Any help gratefully received.