How to change content of Now Playing

Hi,

For Airtime to be of any use to our Radio Station, we need some way to move songs, ID´s etc. in real-time. i.e. the Now Playing List or the Playlist that is currently On Air.

Example: Fred is doing a live show with music requests from the audience, but while he is talking notices that the theme song for his show is running out, how does he quickly make the song repeat or add it as the next item on the Now Playing list?

Thank you for your help!