Why does Recently Played and Sonos Favorites turn to placeholders on Android app?

Sometimes when the app updates, radio stations in Recently Played and Favourites will show as the greyed out thumbnails until you actually play that station again. It happened to me with BBC Radio 2 - it showed greyed out thumbnail but when I played it again, the thumbnail came back and stayed back. 

Edit: with the 16.1 app I saw that there were 20+ old Sonos Favorites that the new app didn’t show at all. I deleted those as well and now the home screen stays on Android. So, seemed it wasn’t the TuneIn stations causing it this time but playlists from Spotify, Apple Music and Amazon Music in Sonos Favorites. Is there an issue that if you have a Sonos Favorite from Music Service X and then you no longer have access to it - the Android app doesn’t handle that correctly?

Playing the stations didn’t help. I then removed all Sonos Favorites and removed TuneIn (New) service. And even though the Sonos Favorites section is completely empty that section in Android app turns to placeholders with no heading text. So currently not possible to access Recently Played either. It initially displays but then disappears. I added one YouTube Music playlist to Sonos Favorites. When the app starts, that is shown in Sonos Favorites but then after 10 seconds that also turns to the empty floating placeholder. 

Is there any other documentation except the API that would explain what the Sonos app is doing and what could possibly cause this error situation? Do I really need to factory reset my devices because of this Android app?

When you spoke of rebooting devices earlier, did you undertake the rebooting one at a time or in parallel? The latter should work much better. i.e.

• Turn off the router and all your speakers/port at the wall.
• Log out of your Sonos account, and force close the app.
• Turn off your phone.
• Turn on the router and let it reboot fully.
• Turn on the Port, then turn on each speaker one at a time, seeing the white light on each before moving on to the next speaker. 
• Turn on your phone. Let it boot up fully.
• Open the app. Sign back in.

See if that helps? 

Interesting to read. The Favs I have added as a temp measure until Sonos Playlists return just don't stay there as don't the Recents. 

This had happened since the early May move to 80.xx.xx I just assumed it was part of app issues/old android (2019). 

Hi, thank you for the clear instructions. I’ll keep them in case I need that in the future.

I did reboot in parallel and did the uninstall and re-install of the app after that. And then the removal and re-addition of TuneIn after that. That didn’t help. 

I then deleted all Sonos Favorites in the Android app. It then showed along the line of “You have no favorites” in that section but still the sections turned into floating placeholders after 10 s from start.

I suspect this time the cause likely were those playlist Sonos favorites - the ones that the new app didn’t show but were visible in the old 16.1 app where I then deleted them. They were from those music services I no longer pay for but they are still as services in the Sonos app. 
 

Unfortunately as I deleted all of those the Android app starred working ok (I.e. Home Screen now stays nicely) and I can no longer debug. If I let go of my current streaming service I’ll then see if this situation is reproducible as I now have playlist from that in Sonos Favorites.

That happened to me in the new Android app since May. But then I realised I had TuneIn stations there and adding TuneIn (New) service fixed that issue. But yesterday’s update broke it again and I resorted to deleting all Sonos Favorites. 
 

I’m fairly sure I didn’t have anything from local library in the Sonos Favorites. I did remove my local library also just recently so perhaps there were something in the Favorites and that then caused that issue with the Home Screen?!

Deleting favorites and Recently Played will fix this? Do I do that on the web app?

Clearly, this is a bug that has existed since May and Sonos needs to deal with it. 

I don’t see an option for removing them in the web app. In the windows app you can remove in the Select a Music Source panel > Sonos Favorites > hover over and from the drop down select Remove from Sonos Favorites. I don’t see Recently Played in the windows app, though.

But I don’t know if the windows app is able to show the old favorites, hopefully it is. I still had the 16.1 app and removed using it. 

https://support.sonos.com/en/downloads

I’d say the Android log stating

System.err: com.sonos.sdk.musetransport.MuseTransportError$TimedOut

in the OP, suggests this has more to do with the controller talking to the Cloud Platform than anything local.

The Sonos cloud api has a number of endpoints for loading and subscribing to favourites. The api reference states “See the x-muse-error-codes extension for a list of muse errors that generate this response” on many of the documented call responses.

https://docs.sonos.com/reference/favorites-loadfavorite-groupid

In my opinion, the grey placeholders are the app waiting for responses or a bug in display from timed out requests. It seems to be the Sonos default placeholder when it’s waiting for remote calls to respond.

Doesn’t make any sense to store favourites on the device and keep writing to the device flash, especially when they are against the household and need to be available to any controller, so I’m not sure what rebooting the router and speakers is hoping to achieve.

Interesting to read last few posts. I've noticed slight changes since posting 10 days ago... (and a couple of app updates & 1 hardware update)

Initial start up of app on android is quicker and menus generate quickly. Can tap on recents and they then scroll down page (then disappear). Tapping on Favs sends them away, so they can't present as a complete list like recents do.

Tiny changes, but agree with. sigh and their thoughts. 

iOS takes longer to generate all menu items, once they appear they don't disappear at all.