I did have the "Always use the default streaming profile..." option enabled. I have now disabled this and can see in the log file that the plugplayer profile is being used. However, the stream URL is still missing ?profile_id=0&convert=mp3.
Looking at the log file I noticed a strange thing that I'm not sure is relevant, the user-agent starts off as "PlugPlayer" but then changes to "RecivaRadio".
107.857: upnp_server_conf::get_profile(701)/4080: INFO: using profile 'PlugPlayer', matching header (User-Agent:PlugPlayer iPhone/10.3.1, UPnP/1.0, Portable SDK for UPnP devices/1.6.6)
109.903: upnp_server_conf::get_profile(701)/2860: INFO: using profile 'New Profile', matching header (User-Agent:RecivaRadio/1.0.0)
I duplicated the PlugPlayer profile and set User-Agent contains RecivaRadio to see what would happen. It uses both profiles but both still use a URL that is missing ?profile_id=0&convert=mp3 .
New log file.
Thanks
Edit: I've just transcoded and streamed successfully to a remote instance of Foobar (using the same profile settings) so I think this issue is due to something weird that PlugPlayer is doing.