Choose a song
Add a song to play during your slide show. First go to Student Share>Koppejan>Music... find a song you'd like to use.
If you're still in Slide Sorter view, double-click on the first slide to go into it in Normal view. Go to INSERT tab... and "Media"...
Go to Audio>... "Audio on My PC"
Browse to Student Share>Koppejan>Music... and go into one of the folders, find the song you want to use... and then "Insert".
Play song automatically
With the song still selected on the slide, go to the "Playback" tab and choose Play in Background. This will make the song play automatically for the entire slide show.
Adjust starting point of the song
Click on Trim Audio and move the green slider to a good starting part of the song. Do not move the red slider!