The mysterious broadcast is the broadcast inviting you to the Big MT. The broadcast enthusiastically invites you to a "Midnight Science Fiction Feature!" while playing a downbeat jazz theme that "makes your head hurt." Newly introduced jazz tunes (including old ones from Radio New Vegas and Mojave Music Radio) are played, so the player can listen to them if they tire of the other Mojave radio stations.
The broadcast can be listened to in nearly any location in the game. In the Sierra Madre, the Courier can select it but no music will be heard.
The songs are set to play completely randomly, because the station does not keep track of the song it played last, meaning that you might get the same song playing 2 or 3 times in a row.
This is the only station, besides the Sierra Madre Broadcast, that can be played while in Big MT. Camp Guardian Radio is blacked out, and all of the other stations are removed from the list and not even visible while playing Old World Blues.
Also, this is the only broadcast that will automatically play when beginning the aforementioned DLC and will stop upon completing it.
pcps3 The song Begin Again is missing from the songs folder. For this reason, the station will go completely silent when it attempts to play it. The station can be restarted by loading an old save.[verified]
pc To fix, open the file "Fallout New Vegas\Data\OldWorldBlues - Sounds.bsa" with "BSA Browser", second you will need to create a folder in "Fallout New Vegas\Data\Sound\songs\" and name this folder "radionvdlc03" extract the file "mus_dlc01_veratheme_01.mp3", and save it under "Fallout New Vegas\Data\Sound\songs\radionvdlc03". [verified]
pcps3 Occasionally the radio station may randomly play when loading an autosave in the Mysterious Cave.[verified]