Yes, the app allows streaming urls to be added to the Sonos system. Exactly how depends on the device you are running the app on. Note they have to be actual streaming urls, not web pages.

You don’t need to disconnect from Tune-In though.

Thanks for that.  I have actually added several URLs using the Windows Desktop App, but because I have the Tune-In service installed they all show up as Tune-In stations and then Tune-in graciously inserts it’s ads.  Anyway, I’ve tried removing Tune-In and it wont uninstall.   I’m suspecting I have to remove the “Tune-In” favorites and try again, then I’ll add back the direct stream urls.  Thanks!

They show up under TuneIn radio in the UI for legacy reasons only: a direct stream is just that, direct. Unless the link actually came from TuneIn of course. Removing TuneIn will not affect the playback of a direct stream in any way.

Direct URLs can be added under the TuneIn menu, then added to My Sonos/Favourites, and the TuneIn service subsequently removed. The links from My Sonos/Favourites will still play.

Make sure you’re playing from the “My Radio Stations” menu in TuneIn, and selecting the custom URL you added. It’s very possible to have two items on that list with the same name, so when I add a custom station, I like to put “(Direct)” in the name, so I can tell them apart. For custom stations, there should be no ads inserted that aren’t coming from the stream provider itself.