@fbartels I found the problem...
I had the my.domain of my Cloudron homepage, DNS-proxied @Cloudflare.
That way TURN/STUN is also proxied and in somekind of way blocked by Cloudflare. I think the problem is it exceeds the Cloudflare max upload policy, when things get over 150MB and are proxied.
As soon as i greyed out the DNS-proxied @Cloudflare, things worked as a charm π
One question left.....
I opened these ports on my firewall for TURN/STUN server to work,
port:5349 tcp/udp
and
port:3478 tcp/udp
Is this the safe and described way to do this?
The ports are redirected to the ip of my Cloudron instance running at home....