Universal Control frequently disconnects between M2 Mac Mini and M1 MacBook Pro

I have a new finding for the problem:

I use Ethernet as my first network-connection on both computers, wifi is active, but not connected.

If I don`t use the build-in Ethernet port of my Mac mini, but e.g. the one of my caldigit-dock, universal control will frequently disconnects again.

I haven`t found any workarounds ...

Tom