Multiple Ip Adresses

[Joly00]

Hello, i have built my Xpenology NAS based on a J5005 Gemini Based Mainboard from Asrock. Everything worked fine until i checked for the Ip adresses in my Router. 

 

First it showed 3 different Ip adresses with 3 different MACs, then somehow i was able to get rid of one, but now there are still 2 different Ip adresses with 2 different MACs.

 

I can change the MAC in grub to fit the one, that gives me the UEFI, but then the both Ip´s just swap their MACs.

 

Can someone tell me, why this is happening and how i can fix this? i dont want to see 2 Ip adresses in my Router.