Played podcasts show up in itunes as partially played

Not sure if this is an iTunes problem or an iOS problem. I have iTunes 12.1.1.4 and iOS 8.2 (though this problem has been going on for a while; I can't remember when it started).

I download podcasts to iTunes, then sync them to my iPad and iPhone. I will usually listen to them on my iPad. Often (not 100% of the time, but I'd say well over 50%), when the podcast is finished playing, my iPad will say that I have no unplayed episodes in that podcast.

However, when I check iTunes, the podcast that I just listened to (all the way through from start to finish) will show up as partially played (the blue dot icon, or whatever it's called, is half full). After a few minutes, if I refresh my podcast app on my iPad, the podcast that I just listened to will show up again as if it has only been partially played. If/when this happens, I'll tap the podcast episode on my iPad, and it will start playing again (sometimes from the beginning, sometimes from some point midway through the podcast). If I then scrub the play bar to the end (so that it finishes), then it properly registers as having been fully played on all my devices and on iTunes. Note that I don't sync my iPad or iPhone with my computer during this time.

Any idea if there's something I might be doing wrong, or if this is already a known issue?