There are bugs in the PS150 2.0.1 network linkup code and the Xerox MFP (286 and DC320 in the PHAROS NZ office)
If the Xerox MFD starts up on a dead LAN port the Xerox auto-negotiate link up creates a default of 10 Mbit half-duplex. If the PS150 is then powered up, the PS150 Ethernet port links up into a bad state that floods the LAN with lots of packets. Set Xerox MFD LAN to 100 Mbit half-duplex.
Future 2.1 release stops flooding network but still links up to a slow speed of 10 half-duplex. We will still recommend configuring Xerox LAN to 100 Mbit half-duplex.