Sound Across Slides in PowerPoint 365 for Mac

After inserting an audio file such as a music file within your PowerPoint presentation, do you want to play music that loops continuously in your presentation, without any interruption as you move from one slide to another? You must ensure that the music clip you are using is suitable for this purpose. A soft music clip that spans across your slides can make the flow between slides smooth, as long as the sound is not jarring or distracting for your audience.

Here's how you can add a music audio clip to play across slides in PowerPoint 365 for Mac:

1. Navigate to the slide where you want the audio clip to begin playing, which is usually the first slide of the presentation. Now, insert the sound clip in this slide, as explained in our Insert Audio (Sound) in PowerPoint 365 for Mac tutorial. By default, PowerPoint will embed the sound clip within the presentation. However, you can opt to link it rather than embed, as explained in the same tutorial.
2. Select the audio icon on the slide, as shown in Figure 1, below.
3. 
   Figure 1: Audio icon selected
3. You will notice that selecting the audio icon makes the Playback contextual tab active on the Ribbon, as shown in Figure 2, below.
4. 
   Figure 2: Format Audio tab of the Ribbon

Contextual Tabs

The Playback and Audio Format tabs are contextual tabs. Contextual tabs are special tabs in the Ribbon that are not visible all the time. They only make an appearance when you are working with a particular slide object which can be edited using special options.
4. The Playback tab offers you different options to control the playback of the audio you have selected. Click the Start drop-down list, and choose the Automatically option, as shown highlighted in red within Figure 3, below.
5. 
   Figure 3: Play across slides option within the Start drop-down list
5. Now, check the Play Across Slides and Loop Until Stopped options, as shown highlighted in red within Figure 4, below.
6. 
   Figure 4: Loop Until Stopped option within the Playback Options drop-down menu
6. With the audio icon still selected on the slide, access the Animations tab of the Ribbon, and click the Animation Pane button, as shown highlighted in red within Figure 5, below.
7. 
   Figure 5: Click the Animations Pane button
7. Doing so brings up the Animations Task Pane, as shown in Figure 6, below. Select the audio file in the Task Pane, and then click the Media Options triangle to reveal media options. You will see that PowerPoint has already set 999 as the number of slides in the Stop playing After text box, as shown highlighted in red within Figure 6.
8. 
   Figure 6: Stop playing after 999 slides

Why 999 Slides?

You find 999 typed in the After text box since that's the largest number that PowerPoint will allow you to add.
8. Rather than following steps 3 to 7, you can access the Playback contextual tab active on the Ribbon, as shown in Figure 7, below. Next, click the Play in Background button, as shown highlighted in red within Figure 7. Doing so replicates all actions taken in steps 3 to 7. To undo these steps, you can click the adjacent No Style button, as shown highlighted in blue within Figure 7. Doing so removes all these settings at one go.
9. 
   Figure 7: Play in Background
9. Whichever option you may have chosen, you will continue to see an audio icon on the slide where you inserted the sound file. If you don't like to see the icon on the slide, you can check the Hide During Show option, as shown highlighted in green within Figure 7, above. Alternatively, you can just drag the audio icon to anywhere off the Slide Area to the workspace area, as shown highlighted in red within Figure 8, below, and your sound shall still play fine.
10. 
    Figure 8: Audio icon moved off the slide
11. Make sure you do so only if you choose the In Click Sequence or Automatically options in the Start drop-down list, as shown in Figure 3, previously on this page. If you choose the When Clicked On option, the audio icon needs to be visible, to click upon!
10. Save your presentation often.