I’m double-nat - not by choice, my service provider is using internal IP addresses, and the fibre modem has no interface that I can access, so I haven’t been able to specify my router as DMZ. So even DDNS doesn’t work, and my ubuntu server can’t be accessed from the internet/not publicly accessible.
Hopefully someone has a work-around, otherwise it looks like I’m screwed if that is the only way to play an mp3