Podcast count discrepancy

When I select Podcasts in iTunes, it displays a total episode count as 213 episodes, taking up 10 GB worth of space.

When I created a Smart Playlist with Media Kind > is > Podcast, it displays 806 episodes. Some are 1 KB files that I already played and they should have been deleted. Most, however, are the full file size, adding up to 42 GB worth of files.

These have also been played (except the 213 noted above) and the Last Played column and Get Info confirms their Played status. Selecting one of these podcasts does not give the option to Delete them. Get Info does show the Finder path to the episode, but the Podcasts folder in Music > iTunes does not contain the file.

Show is set to: Unplayed/My Episodes and Saved).

Settings are set to: Delete Played Episodes.

My questions:

1. I'm having huge problems with Podcasts re-downloading old episodes as if they have not been played, over and over again.

Is the above discrepancy a possible, or even likely, cause of this.

2. How do I clear this mess?

Unsubscribing, their re-subscribing the podcasts had no effect.

Changing the Media Kind to something other than Podcast, so at least I can delete them doesn't help, as these deleted episodes will muster-appear.