I'm listening to the Podcast app and I stop the app. Some time later, I get a call. I answer the call, finish the call and hang up. Suddenly, the Podcast app begins playing again over the iPhone's speaker. If I was listening to the Podcast app then was interrupted by a call, then it makes sense that the podcasts resume playing when done with the call (I actually like this feature) but it doesn't make sense when the Podcast apps were stopped before receiving the call. The Podcast app randomly started after dictating a text message using Siri as well.