Google Slides Insert Audio File. Before you add any audio, please note that Google Slides only works with audio files stored in your Google For example, you can determine whether the audio plays on click or automatically. For many years, teachers have been asking me how to add audio-usually narration or background music-to Google Slides.
In order to do that, go to Insert > Video.
I cannot find any documentation on how to insert a file through Google Scripts but can do so going through the available menu options.
Google has somewhat recently rolled out the ability to insert audio files from your Drive into Slides with various playback options. Google Slides doesn't support adding audio files to presentations, but it does let you add videos. I would prefer Drive since the playback won't include any pre-roll advertising.