When you record narration in Articulate 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 with Storyline's sound tools.)
When you publish, the MP3 files get re-encoded at the audio bitrate you specified in the quality settings:
- Standard uses an audio bitrate of 48 kbps.
- Custom lets you select an audio bitrate between 16 kbps and 160 kbps.