I would perhaps first try a reboot of the local router and just see if that fixes the issue. 

Having the same issues this morning. NTS played fine yesterday. 

I didn’t know what NTS is, but I just added it to my S2 system and it works fine. (In the US).

I’ve re-added to my S1 system and it fails.  It recognises the correct radio schedule but when you click play it just reverts to stop. 

I would recommend that you submit a system diagnostic within 10 minutes of experiencing this problem, and call Sonos Support to discuss it.

There may be information included in the diagnostic that will help Sonos pinpoint the issue and help you find a solution.

When you speak directly to the phone folks, they have tools at their disposal that will allow them to give you advice specific to your Sonos system and network.

Looks like NTS may no longer be compatible with S1. I just tried to add it to my S1 system and it could not. No problem with adding to S2.

I can’t play any of the NTS channels through my Sonos S1 Controller. Anyone found a workaround? This can’t go unfixed can it? That would make so many systems out there incompatible. Not that NTS is a massively listened to service but seems crazy the S1 hasn’t been thought about.

Its not that crazy. S1 users are less than 15% these days, declining literally every day. Mind you, the fact that S1 is the cause is speculation by me. You should contact NTS directly to confirm.

Understood about the low usage of S1 but I’m not actually able to use the S2 controller as I am using a Sonos Play 3 speaker and I don’t believe it is compatible. 

The PLAY:3 is compatible with Sonos S2 operating system. I’ve been using a pair of them operating under S2 since it was released. 
 

See here.

I’ve just deleted the S2 controller I had on my Mac and re-downloaded it and you’re totally right, now works with my S3. The app icon is different (this has rounded corners rather than sqaure) so some updates must have happened or I was using a really early version? Either way, very happy, thanks for the support. 

Yes, the app icon is different, so you can tell the difference between S1 and S2 at a balance, probably for those who need to run both systems.

It’s possible you hadn’t been updating properly, hard to tell. Sonos does release updates relatively frequently, even for S1, which is down to bug fixes at this point.

Glad you got updated properly. Enjoy NTS!

A week later, and it’s still not working.

This seems to be a problem with the S1 System. The issue seems to be with the system suddenly not being able to connect to NTS’s HTTPS stream. I’m not sure what’s going on, but it might be a HTTPS certificate problem on the S1 system, or the systems clock. I’d like to investigate further, is there a way to get a terminal shell for the S1 speakers so I can look at the logs? 

For now, I found a work around that will hopefully help other S1 users like  @JamesGold  and @ric_bell . This solution will work unless NTS stops offering streaming over HTTP. 

1. Add the service “TuneIn”. 
2. Go to the Service in your sonos s1 controller program
3. Go to “My Radio Stations”
4. Click “Add New Radio Station”
5. Name it whatever you want and use the Following addresses for the streams
   1. NTS - http://stream-relay-geo.ntslive.net/stream
   2. NTS2 - http://stream-relay-geo.ntslive.net/stream2
   3. NTS Slow Focus - http://stream-mixtape-geo.ntslive.net/mixtape
   4. NTS Field Recordings - http://stream-mixtape-geo.ntslive.net/mixtape23
   5. NTS 4 to the Floor - http://stream-mixtape-geo.ntslive.net/mixtape5

If you need help adding other stations let me know, most of them are mixtape followed by a number.

I hope this helps someone. Still no idea why it just randomly stopped working on the system. When I first tried this solution, I was trying to use https and they still wouldn’t work. It wasn’t until I used regular http that I got it working. I don’t know if they are doing anymore S1 updates that could fix this. But it’s almost certainly an HTTPS certificate issue.

Thanks so much for this .

Hopefully they can sort the certificate issues out, but until then this workaround is great.

Really appreciate your help @laind. 

Super helpful - thanks man.

Have you got the https link to the poolside stream?  cheers

Just adding my voice here as I also have this issue. Thanks to @laind for the workaround.

While I’m here and given that you’re all obviously my people, you might like my workaround for playing old NTS shows on Sonos https://www.reddit.com/r/sonos/comments/q496fu/comment/il7dq16/?utm_source=reddit&utm_medium=web2x&context=3

@Gezzzz 

NTS Poolside - http://stream-mixtape-geo.ntslive.net/mixtape4

Hey SONOS - has this been fixed properly now or do we still have to sue this workaround? would be better to have it working the way it’s supposed to..

just to say TUNE IN is rubbish and full of ads..

Can you teach us how to locate the streaming url with these mixtape numbers? I’d like to add Expansions and The Tube infinite mixtapes, but I’m not a skilled digital sleuth to decipher where these geo stream url addresses are hidden. Thanks so much!

This issue is very frustrating. Are there any other radio services available on Sonos 1 that can stream NTS?

@dpoison TuneIn should only play an ad when starting a new stream. If you hear more ads the stream is interrupted, which could mean wifi problems.

UPDATE: The latest software update that came out for the S1 system today 01/27/2023 fixed the issue for me, my NTS stations are working again. Thank you Sonos. 

The easiest way to do this is to have the google developer console open to the network tab, and see what file loads when you click the “play” button on a website with music. It should list either a .mp3 or .m4u, you can add this URL to your tune-in playlists. hope this helps!