b2evolution has support for podcast hosting.

Just upload the mp3 file to your server (or CDN), enter the URL of the mp3 file into ‘Link to url:’ and select Item Type Podcast (which is preconfigured to treat the URL as podcast here).

This will produce 2 things:

• In the front-end, the Link to URL will be rendered in a Player (depending on installed Plugins)
• In the RSS2 feed, it will be reference in an <enclosure> tag