Clients are stopping connecting to Appletalk printer

[sidewinder]

Had a call from the Art department yesterday saying that their Macs had stopped printing to their network photocopier (Photocopier is a Canon 1100 and the network unit is a Canon PS-NX500W)

What was happening was that when people were printing, osx was trying to open the appletalk connection and was failing with an error of 'no such host' or something similar (stupidly didnt write it down - im worse than a teacher!)
So I deleted it and attempted to re-add it. The printer would show up in printer browser (shows up as 3 - CANON1100_Direct, CANON1100_Hold, CANON1100_Print) but clicking on it would bring up the 'Opening connection' dialog as it attempted to connect, but it would time out every time.

So we rebooted the network unit and all was OK for a while, but then it started happening again. I was told it was now happening on a different set of Macs, that all had Panther (the first time they were just trying to print with iMacs that have Tiger)
But this time a few let me delete the printer and re-add it straight away, but others were timing out trying to add it

Went over and tried after school yesterday and again the iMacs were doing it.
Now Ive tried with a MacBook over here, which wasnt connecting to it yesterday, and now it is, every time, which is why I cant post the exact error messages.

I cant get into much of the printer config, the web UI is a complete waste of time, and theres no obvious 'settings' section on the menu on the network unit - theres a 'Run Setup' but that sounds a bit dodgy to me, at least until I can find the manual and check its the right section

But nothing has changed, so why is Appletalk behaving so strangely all of a sudden??

[sidewinder]

Now im looking on the Mac server (running 10.3.9) and getting the printer list up, and it finds every other Appletalk printer but not the Canon one!
Yet Ive got the Macbook next to me and it finds it every time!

Whats going on?