If you want to add a Download button to download the file directly, try the steps below:
1) Install and enable DownloadFile module - https://www.drupal.org/project/download_file
2) Add a new audio field in this Views
3) On this audio field, set the "Formatter" to "direct download file" or other options provided by DownloadFile module and save your view.
Now, when you click on the file in the Views listing page, it should download directly the file. But mind you this only work in the Views layout explained in this particular video, which is "Music Library 2".