Old podcasts added back as new when syncing iPhone

I have my iPhone and iTunes set to not sync any podcast subscriptions, so that all my podcast data is stored on my phone and not my computer. But since the Podcasts app was updated for iOS 7, whenever I sync my phone a few old podcast episodes get added back as unplayed episodes, even though I've listened to them on my phone and they've been automatically deleted. Also, new episodes that I haven't listened to are often deleted when I sync, so I have to go back into the catalogue and re-download them.

Any ideas on how to keep this from happening?