Have you tried using the podcasting feature on your MIX yet?
Just add the podcast URL you want as you would a regular RSS feed on your page. Give it a go - either select from the suggestions in the podcast directory provided, or paste your favourite podcast URL into the "Add Feed" box. Clicking on the listen button that appears when you've selected your podcast of choice will automatically bring up the MIX audio player, located where the search bar on the top of the page is.
If you're after more information about podcasting, take a look at the Wikipedia description for some background reading. The BBC also has a good podcasting tutorial, along with a list of their audio programmes that are worth a browse.
Let me know if you've found any good podcasts worth a mention!