Go to Custom Fields > Tools and import this (mirror) field group.
This should import a "Audio Meta" field group having mp3 and ogg custom fields (both set to return URL). Ensure that the field group is attached to the audio CPT.
Go to Audio Tracks > Add New.
Add your audio post type entries with Title, Content, mp3, ogg files and featured image for each.
Go to Oxygen > Templates.
Add a new template named say, "Audio Archive".
Apply it to audio post type archive with a priority of 1 (or more depending on how your template for sitewide archives is setup).
Edit it with Oxygen.
Add a Section. All the following elements are to be added inside this Section.
a) [optional] Add a Heading element.
Double click the placeholder text, click on "Insert Data" button at the top and click on "Archive Title". This will replace the text with dynamic title of the post type archive (once you click off of the element).