Spool Service & High CPU Usage

Running a W2K Server on a small network with about 15 users. Serving up 4 network printers – 3 Kyocera FS-C5020N’s, and an HP2200. Since adding the Kyocera’s to the mix, I’ve had problems with the server performance degrading – with the spoolsvc.exe service using the majority of the CPU.
Any ideas on what might be causing the problem, and how to determine which client may be the culprit?