Option 1: RSS Feed - Use a service like Podbean that produces and rss feed and use that feed in the app! (This option will use the native Media Player on our platform)
Option 2: Host the .mp3 file - If you host the actual .mp3 file online where you can use the URL for the file ex. (This option will not use the native Media Player on our platform.)
Option 3: Live Stream - Use a live streaming service that can stream audio and use the "Live Stream" Module in the app. Either one of these will work no problem for you.