Hello, I'm having similar symptoms. Version 11.12., premium on LaunchBox & EmuMovies
For me, I added Playstation games much later than everything else. Download Metadata & Media under the platform isn't giving any new images/videos, but I've been finding that going into Edit for individual games can get lots of media that isn't already downloaded. When I go to All Games and do Download Metadata & Media, it's saying there's something like 16,000 files to download, but keeps only getting through a few dozen before running into the 404 loop. It's followed that same pattern about 10 times, and did this to a lesser degree on a prior version (sorry unsure which).
Debug 2021-06-25 05-35-48 PM.zip