jackcaron on "[Plugin: Sermon Manager] 404 error using Sermon Module since WordPress 3.6.1 update"

I am having an issue with iTunes not picking up any new sermons posted since the latest WordPress update (3.6.1) around September 12, 2013. Since that time my feed has been returning a 404 error through feed validator but it is reading OK in my other feed readers such as Chrome and Apple RSS reader. I had not changed any settings and then last week I noticed iTunes had not picked up the sermon from the previous week so I assume it has something to do with an update. Anyone else having this issue or any suggestions for a fix?

http://mountainviewbible.com/feed/podcast

http://wordpress.org/plugins/sermon-manager-for-wordpress/