When you have multiple audio and video files in a project you are trying to render your project. Project is rendered and at the end of rendering software is returning an error saying "Export Audio Chunk Complete With Errors". When you check the exported video file, it doesn't have any audio.

If you encounter an error like this, there could be 2 possible reasons behind such error. 

Reason 1: Any of the audio or video files used in the project was still open on another app or a media player.

Reason 2: You didn't save the project properly before starting your render. 

In this case, please follow these troubleshooting steps:

1. Make sure the audio and video files used in the projects are not being used by any other app or opened in a media player during export. 

2. Make sure you properly saved the project before attempting to export.

3. If you still get the same error after export, please save the project on close, restart the software and retry exporting.