Hi! Regarding your suggestions:

1. Not using a wired connection for all stations/nodes (e.g. connecting a laptop to the network via WLAN)
Only network connection is PC to Node via CAT6 wire. I even disabled any other network connections (Wifi)
2. having the same IP-range on several network-adapters on one station (e.g. both WLAN and LAN starts with 192.168 etc)
Didn't know that, and for a minute thought it could be the problem, but then again i disabled the Wifi adapter, and the only other adapter on my PC is the one that i'm using to connect to the Node. Still, i cannot change the IP-range of the Node since i need to enter the setup interface to do that.
3. Windows Firewall is enabled and not properly configured
I disabled windows firewall, and i allowed communication with all MA realted applications anyway.
4. 3rd party Firewall is enabled and not properly configured
I have no other antivirus or firewall
5. Using switch or router that blocks or redirects multicast traffic
Connection is straight from PC to Node, i'm not using any Switch or router

Idk, maybe the Node has some kind of malfunction and i'm running around in circles for nothing... Thanks so much for your help anyway!