Preferred IPVersion only is about DNS resolution and connecting to our relay server. Has nothing to do with direct connections.
Under linux tcpv6 and tcpv4 sockets are shown as tcpv6, see
unix.stackexchange.com/questions/237731/why-are-ipv4-tcp-connections-showing-as-tcp6
you will only see two entries if you bind to ipv4 and ipv6 in seperat!
I would recommend we take a look via Teamviewer, contact me via
support@jdownloader.org
Are you running FritzBox router? or any router that blocks DNS rebinding?
see
https://support.jdownloader.org/Know...ode---fritzbox