There’s another thread about this. As a guess, the issue is on TuneIn’s servers, since that data never exists on a Sonos server. You may want to contact TuneIn directly. 

Thank you for reply. It’s quite strange because by internet browser the content is reproduced correctly.

As far as I am aware (my contacts within TuneIn have been gone for years, now), TuneIn uses a different server connection to feed Sonos than they do for their own app, and the web. 

I wrote to TuneIn assistance, waiting for their response

Same issue here. I reported it to Sonos but got nowhere; they put it down to me having a free account despite it working okay in the TuneIn app and working fine via Sonos until recently. 

Sonos wouldn’t be able to fix an issue on TuneIn’s servers, you’d need to lean on TuneIn. 

I’ve done that as well! 

 Same issue. Although for a while I got an ad as well. Please post answer from Tunein if it resolves problem

Podcasts now seem to be working again…. TuneIn have got back to me and said it’s a known issue that their developers are working on; apparently it’ll be fixed in a future release….  I hope they don’t mean the TuneIn app, I did make it clear it was only an issue via the Sonos app! 

I would assume it’s the software on TuneIn’s servers…or wherever TuneIn points to to get the data. To my knowledge, none of this ever lives on a Sonos server, so it wouldn’t require an update to Sonos’ software/firmware.