Current mechanism is to access roonlabs.net,then the roonlabs using access IP to access Roon Core.
I use the openclash connect internet (VPN is similar) , so the Roon ARC test always fails.
If a config the openclash to access roonslab.net directly, then Roon ARC test succeed.
So I think Roon ARC can provide a feature to specified the Roon Core domain name / IP, so Roon can access Roon Core using specified domain / IP.
Otherwise, Roon ARC can not be used when roon core is behind a VPN or other similar situation.