AnyDesk connection drops with status “anynet_unknown”

Problem: connection from an Anydesk PC client to a macOS AnyDesk instance drops after a few seconds/minutes with the the following error message:

AnyDesk for Windows version v5.4.2
AnyDesk for macOS v5.4.1

According to Anydesk support (https://support.anydesk.com/FAQ)

Unexpected session ends, disconnects, session interrupts after a certain time
Sessions may end unexpectedly for various reasons. If you encounter interruptions after a specific amount of time into the session, go to Settings and switch to the Connections tab. Disable direct connections. You may also setup a listening port in your firewall for AnyDesk in the Security Settings (https://support.anydesk.com/Settings#Security)

macOS version doesn’t currently offer the “Direct Connection” option but Windows does: https://support.anydesk.com/Settings#Connection

 
Remove Direct Connection and should work again. I liked more the idea of having a direct connection. However, that’s a different investigation to carry out, if one wants to. At least now I know where the following investigation needs to start from

Update – 15th of January 2020: in the meanwhile AnyDesk for macOS v5.4.2 has been resealed and by allowing direct connection on both macOS and Windows on port 7070 connection seems to work properly. This latest macOS version adds the direct connection option to the software

Update – 8th of February 2020: should happen again, check the local port macOS side. It seems to be randomly losing the setting, reverting to port 0. When that happens, the problem starts all over again