I’m happy to adopt a new podcast app if it has sponsorblock natively or through a plug-in. Otherwise let me know if there’s some other way to make it work. I don’t see why it wouldn’t work as all of the segments tagged for skipping are crowdsourced which would also work for Podcasts.
So without having looked into it really, my assumption is that these podcast hosts will serve a specific file based on the response to an API call. If my Pihole blocks that call, they don’t want to serve nothing, so they fallback to a file that sometimes has “generic” ads (often for US-based companies) or other times no ads at all. Of course this doesn’t work for all podcasts, and as mentioned sometimes still has ads anyway. One day I might look more closely into it.
Ah, I assume the audio file is being put together server side and customised to the downloaders locality. The pihole is likely obfuscating that and causing a default version to be downloaded