Need help setting up jitsi-docker behind firewall+proxy

Hi Everyone,
I need help setting up Jitsi on a server, which is behind corporate firewall and proxy.
I am running the docker version.
I don’t need it to be accessable from the internet, but within the company network/vpn.
I disabled JVB_STUN_SERVERS.
I am able to access the website, but when I try to create a meeting I am getting disconnected immediately.

Thanks and warm regards,
Ben