Current android build.
Kind of error: “null”.
The URL to the Youtube video (which is embedded on the WEBSITE of the podcast) gets mentioned.
Podcast at hand: Liebe zur Musik: Frederik Wiedmann im Podcast ("Star Trek: Picard") - News & Stories
(Listeners get the podcast RSS style. But apparently the app does not just load the podcast but also its website. And on its website there is a YouTube embed as part of the “further information” thing. The embed is crucial. But the app aims to read it as well. Do we add some sort of #ID in the html for the app to ignore that part? How do we solve this?)
No Antennapod user can download the podcast episode. All other podcast/RSS apps we tested work fine with this episode.
And when the podcast is an mp3 file and if into the shownotes a YouTube video is embedded, the app aims to download the YouTube embed (when clicking DOWNLOAD PODCAST) instead of the podcast mp3 
Contact the podcast creator. AntennaPod downloads whatever the podcast feed tells it to download. Apparently that podcast feed has the YouTube embed in the download url.
answer bellow, i messed up here
It has the YouTube embed IN the download URL?
The feed says, quote:
<enclosure url="https://www.trekzone.de/podlove/file/916/s/feed/c/mp3/ZV023_Frederik-Wiedmann.mp3" length="105795030" type="audio/mpeg"/>
THIS is the podcast, not the media content in the shownotes.
UPDATE! I know what it is! Sorry for my complaining! It’s RANK MATH. It messes with the feed.