I have a Dell 1320c Laser printer which is networked, but the problem seems to be across the board with all PC's

1 x Laptop running Windows 7 Ultimate
2 x Base units running Windows XP Pro
1 x Base Unit running Windows Home Premium
1 x Base Unit running Windows Home (standard edition)

When trying to print a file in any format (pdf, xps, dos, rtf e.t.c) it will print the first couple of pages of the file then the amber lights will start flashing on the printer (exclamation mark & paper tray), even though there is enough paper in the tray, if I pull out the tray and put it back in, the job will start from the very beginning and print out what it already printed then lights will flash again at the very same place, if I press the cross to cancel the print job then it does exactly the same, even if I go into the printer job folder and cancel the print, it carries on printing the same couple of pages, this seems to be a problem with files over 4 pages in size, anything below this will print without any problems, all PC's are running the current drivers for the Dell 1320c so drivers are all up to date, I have also updated all windows through the windows update site but the problem is still persisting.

Any help with this would be greatly appreciated, even trying to print the file a page at a time it still on occasion  flashes up with the exclamation mark and paper tray icons.

All pages that it prints come out in perfect condition so no problems with cartridges