I want to use foobar to stream music from my KODI multimedia system.
For this I have added a user specified upnp server to the configuration.
http://<server name>:2002. The port is forwarded on my router pointing to the KODI system.
All works fine in a local area network where it finds 2 servers one local and one user specified. However outside the local network it fails to play. It still finds the KODI server (the user specified one), displays the albums and tracks etc, but it just fails to play.

The foobar console shows:
Opening track for playback: "http://<ip of the KODI system>:2002/%/<idofthefiletoplay"
Prepared skin: (1334*750)
Prepared skin: (750*1334)