The 'listener' functions are disabled if an extension is loaded while a radio stream is playing
If I start playing a remote radio stream and then load my extension, the "input_changed()" and "meta_changed()" functions aren't called during any subsequent track changes.
Perhaps only "meta_changed()" should be called in this case, but right now I'm seeing neither of them. I've attached an extension that will allow you to test out this issue quickly.