Digital BW, The Print

A friend has two 1280s on a G4 with OS 9.2, one for icc piezotones and
one for color. This has all been working fine for months. Nothing new
has been installed, no new devices have been connected. There is a USB
hub, but it's always been there. Suddenly, part way into a print, he's
getting the following alert about 20% of the time, and has to abort-

Communications error has occured, turn on or restart printer

Needless to say he's wasted a lot of paper. It seems like a USB error
to me, but I can't seem to nail it down, there are no new USB extensions.
Any advice?
Thanks,
Tyler