MinimWatch problem on Mac mini 2018

[gsimjansen]

I did not install MinimServer on the new Mac mini. MinimServer runs on my NAS. I have problems with MinimWatch not discovering MinimServer on the NAS. In my browser I see MinimServer running and I can do a rescan from there.
There is no firewall and I tried everything mentioned in the troubleshooting section. Minimwatch discovers MinimServer when running on other Mac's in my setup. Therefore I think something in the new Mac mini causes the problem for Minimwatch. The new Mac mini has the T2 chip which has various settings for security. Changing these settings does not help either. So I am stuck. That's why I asked here for help:-)