Q. How can I include captions in a PowerPoint audio recording?

PowerPoint has an option to record audio so that narration is attached to each slide in a presentation. Unfortunately, PowerPoint does not offer native support for captioning voice narration. You'll need to install an add-in or work around this limitation -- or such is the official advice. Below documents some of the official steps integrating some of the troubleshooting this librarian had to try -- and it still wouldn't produce functioning captions. 

The built-in accessibility inspector, however, will still flag the missing captions as an issue:

Some relevant excerpts from Microsoft Support:

You can add captions to presentations that you've recorded with video narration, screen recordings, and any other video (except online videos) that you insert into PowerPoint. Currently, adding captions to an audio-only recording isn't supported. [emphasis added; other support pages will say captions for video and audio are supported before going on to give steps that only address video, for the record]

To add captions to an audio file you should use the STAMP add-in. For more information, refer to the Office 2010-2013 tab of this article. 

Further, PowerPoint doesn't natively create the caption file. Microsoft has instructions for manually creating a .vtt caption file with timings in a Notepad file; otherwise, they recommend searching online for a caption tool. The STAMP add-in will help you create timed captions.

STAMP add-in

Follow the Microsoft instructions to check your install of PowerPoint and install the add-in. (Note: their instructions are a little outdated: the download only has one current version that comes in a .msi file. You don't need to determine which bit version you have nor unzip the file.)

Troubleshooting

In this librarian's experience, clicking "create caption" did nothing, even though the other things worked. This thread on the add-in support page was helpful in resolving that. To elaborate:

1. In the Home tab, look for the Editing group > Select > Selection Pane.   (Keyboard shortcut: Alt + F10)
   
2. Double-click the audio recording(s) to edit the name to end in .wmp. 
   
3. While you're here, ensure that your slide contents are in a sensible order for screen readers, which read content in the order they were added to the slide and not necessarily how we see it. 
4. Try launching "create caption" again -- it should be able to recognize the audio and launch the tool properly.
5. Resume following the Microsoft instructions for creating captions.

More Troubleshooting

If you can't get playback in the "create caption" pane, try right-clicking your narration icon in the slide and choose "save media as." Delete the icon/recording, then re-add from the file you just saved.

Other Options

Video Recording with Live Captions

Now, when you present your slideshow, PowerPoint has an option to include live captions as you speak. You could also get the same effect by presenting to yourself in Webex or Zoom with captions enabled. 

However, automatic captions alone are not sufficient for accessibility requirements. They often "mis-hear" what was said which can create significant and confusing errors in the captions, and they typically won't be punctuated correctly, creating run-on or awkward sentences. You need to be able to edit the captions.

So What Can You Do? 

• Take the time to write a script for what you want to say and paste it into the Notes section for each slide.
  • Don't like scripting? Narrate into Word's speech-to-text tool. Clean it up as needed, then read from it for your PowerPoint narration. Share the Word doc as a transcript or paste into the Notes.
• Record your presentation as a video so you can include captions for each slide.
  • Yuja Captioning
  • YouTube subtitles and captions [YouTube videos can be kept unlisted so that you can use them in D2L without the entire world finding them]