Microsoft PowerPoint support:
(copied from the website)
Play music for the duration of your slide show
Applies To: PowerPoint 2016 PowerPoint 2013
To play a song in the background of your slide show, do the following:
On the Insert tab, select Audio, and then Audio on My PC.
In the file explorer, locate the music file you want to use and then select Insert.
On the Playback tab, select Play in Background.
Play music in the background
TIP: If you want to use music from the web, download it to your PC before you use it in a presentation.
Do you want to play multiple songs across multiple slides?
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