When you record narration in Storyline, MP3 files are generated with an audio bitrate of 192 kbps. These audio tracks are stored in your project file. (Tip: To make a backup copy of your narration or use it in other projects, export it from Storyline 360 or Storyline 3.)
When you publish, the MP3 files get re-encoded at the audio bitrate you choose in the quality settings.
- Standard quality uses an audio bitrate of 56 kbps.
- Custom quality lets you select an audio bitrate between 16 kbps and 160 kbps.
- Optimize Audio Volume normalizes audio throughout your course for consistent volume across all slides. If your course audio already has consistent volume, you can speed up the publishing process by unchecking this option.