We are using Wordpress 3.7.1, but we've been using that for at least several weeks. The issue didn't occur until sometime over the last few days after the Jetpack 2.6 upgrade.
I just tested a page with literally only an audio shortcode and with Jetpack enabled it gives the 500 error but works fine with Jetpack disabled.
Here is the shortcode I used:
[audio src="https://dl.dropboxusercontent.com/u/154257140/Sermons/2013/Sermon_12012013.mp3"]
If it is not a bug in Jetpack 2.6 then the only thing I can figure is that the plugin is corrupted. How do I completely uninstall and reinstall Jetpack including any database data?