Unable to clear the queue when created by 3rd party apps

That might be the case, but regardless of how it was started, the music is playing on a speaker in the Sonos system. The Sonos app should be able to at least clear the queue on that speaker.

 There is no real queue to clear.

Not sure what you mean by that. In the Sonos app I click on the “queue” button. The view is named “Queue” and there is something in the queue that I cannot remove.

For a user it looks like there is something in the queue, and useability is what Sonos should care about, I think. Technical details about what might or might not be going on under the hood is not something a user should have to care about. The user interface says “Queue”, and how different use cases for the queue is handled in the code is not my concern.

It is the problem with streaming direect to a device. I just add a track from my library to the queue and then it lets me delete the queue

 What I meant was it’s not a list of tracks.  It just shows large box showing what service was last playing and what’s playing under that.  Once you change the play-to device in the service the option to look at the queue disappears.

 The way I tested this was with Spotify Connect.  I chose a Sonos room in Spotify, started some music and looked at the queue to see the pane with the Spotify logo and under that the track playing.  Next I went into Spotify again and chose my phone as the device to play to.  Last I looked back in the Sonos app to find the Now Playing screen had “No Content” showing and no queue icon was available to access.

 Now if I only stop the music in the Spotify app the Now Playing screen does still show what was playing in a stopped condition and the queue does still have the pane with the same info.  Only when I change the play-to device in the Spotify app does the queue and Now Playing screen clear.  Of course once you choose something else to play that Spotify pane will be replaced by whatever you have chosen to play next.

 I’m guessing you would like to clear the queue when the condition is the one described in the above paragraph.

Yes, there have been situations when that is what I wanted to do, and I was surprised I couldn’t do it. I don’t remember how this worked in the “old” app, and perhaps it was the same behavior. Still, I don’t remember reacting to it before the “new” app.

And I know I can “clear” the queue by selecting something from within the Sonos app, and it is not a big deal. But it still feels like this is a weird behavior.

 Tried it in the old app ( have on an old iPhone 7 ).  It gives you an “End Session” option rather than the traditional Clear option.

Something similar in the new app would make sense I think.