As I was actually in front of an MC for a change, I had another look at this for you.
Now, I never really used MC this way, so I'm not sure if this is a bug or not, but, the issue you are describing is NOT limited to BBC streams.
Local files do not play either.
From the Windows Run dialogue,
MC22.exe /play "D:\Music\flac\Admiral Fallow\Boots Met My Face\11 - The Sad Clown Cast.flac"
Does nothing other than launch MC, and
add the specified track to playing now. Nothing else.
With MC already running, a second run of the command
replaces the playing now list, and playback begins.
This is the same regardless of the target being a BBC stream or a local file.
A developer will need to chip in now as I am not sure if this will be considered 'broken'.
A workaround, if it helps, is to run media server. Set it run at Windows startup (Tools > Options > Startup> Windows Startup > Media Server). It places a low footprint MC running in the system tray (or notification area I think they're calling it now
) and then, "MC22.exe /Play" will work as expected. Not ideal, but might at least get you running untill a developer can respond?
-marko.