Network Rendering wrong MAC Adress

[techdoku]

i am using KS 5.1 and network rendering 5.1 (64 cores).

sending jobs to the key worked fine with 5 slaves and 36 cores.
i added one more slave to get in use of more cores 
then the network rendering crashed.
i tried severel times and it worked again BUT only for ONE job. after finishing one job NR can not find a master (AUTO). 5 minutes later the muster is found and either the job finishes or it failes.

I found that the last slave wich was added has got the same MAC adress as my slave (master/slave).
But even the mac is equal in NR - under the pc network settings under IP adress ther is a different MAC adress on my master and the slave.

so where comes the 2 "equal - wrong" mac adresses?

everything clear? 

[techdoku]

could it be that the name of the hosts make this problem?
my pc name is 004 and the other pc is named 040!
all the other hosts are 097, 096, 025, 055

[thomasteger]

Mac address or IP address?

[techdoku]

MAC!