Networking Doosan Mynx 5400/50 help

Hi,
we have 3x Doosan machines on the shop floor. We are trying to connect them to the network to allow us to save files onto the server and also pull programs between machines without the requirement of a memory card. we have successfully connect 2 of the machines but are having issues with the 3rd.

From what we can tell we have mimicked the settings from the other machines.
I have tested the Ethernet connection and it is working fine.

The machine in question is a Doosan Mynx 5400/50 I series
we have parameter 20 (i/o) set to 9.
Unique IP address used.

when i check the Com state:

Baud rate 100mbs / full duplex - this flashes on and off
all other state 0


Any help on this would be greatly appreciated