Looks like you have the "Stop after this track" option enabled, so it stops after playing the track. In this case, silence detector will not action because it stopped for a legal reason.
This option was not enabled, you can see in the video that the button is NOT in this way
It is very strange but I tried to play the previous video and now the playback starts. (See new video).Error messages about server connection does not affect the playback - the disconnect occurs when you have nothing playing, no data is being sent to the server in this case and the server breaks the connection. You can make RadioBOSS send silence when nothing is playing, the option is located in Settings->Playback.
But you can see how the encodec stops, even though the option you comment on is enabled