Hi @caesar327.

Thank you for reaching out.

This is really odd that the album art is not showing properly in your Sonos application.

Here are Sonos album art limitations:

• album cover should be up to 320kb in size on iOS and Android (with no resolution limit).
• JPG, GIF, PNG, BMP supported for the embedded images.
• JPG & GIF supported for folder.xxx (only one folder.xxx file per folder).
• If both embedded image and folder.xxx exist, Sonos will use the embedded image.

You may also find this support document-link worth a read. Missing music library album art in the Sonos app.

Let us know if it works. If you need help with any other information, please be sure to let us know.

To clarify, the album art is NOT from my own Music Library, so I don’t control the sizes or types of images.  This is from songs added to My Sonos from Apple Music and/or Amazon Music directly. 

Also, keep in mind that the art displays correctly in a track list, in a play list and while the music is playing on the “now playing” screen in the Sonos app.  So it must be the right size/image type.  So something else is going on here. 

Why would an Amazon Music song display art in one part of the Sonos app, but not another?  As I mentioned, it generally fails to display (on certain songs/albums) only on the “My Sonos” main screen (the screen you see when you press the STAR button.   But it displays correctly within a Sonos Playlist, within a Sonos track list of the album, and when actually playing the song (on the “now playing” screen).

Also, keep in mind that this happens with different songs that are part of the SAME album.  As an example, see below screenshot for the song “Yer So Bad” by Tom Petty.   It is part of the same album as the song “Runnin Down a Dream”.   Yer so Bad does not display art on the song list, while Runnin Down a Dream does.   Also, as you can see, simultaneously, Yer So Bad IS displaying correctly on the “now playing screen” -- shown in mini version on the below screenshot (playing to my Office Sonos One):

Hi @caesar327.

Thank you for replying back to us.

Can you also check if there’s any pending update for your Apple Music & Amazon Music application, make sure also that your phone software is up to date.

How about other music subscription? 

Might as well submit a diagnostic report. Not sure if this is also related to your music subscription also since I tried to search the apple community and there are a lot of customers reporting the same issue.

Let us know if it works. If you need help with any other information, please be sure to let us know.

Interestingly, I opened up the Sonos App on my PC, and it populated the missing album art there.  I then went back to the iPhone app, and the art was now there.   So somehow, using the Sonos App on my PC (which I rarely use), “fixed” this.  We’ll see if its permanent or something temporary.  But I assume this isn't expected behavior within/between different forms of the Sonos app?

Hi @caesar327.

Thank you for your feedback.

That's odd that your album art now all sync after using the app in your PC. we will go ahead and further investigate this, we will update the thread if theirs any new update related to this concern. 

If you need help with any other information, please be sure to let us know.

All controller apps cache album artwork locally. Generally a PC can get the art more quickly than a mobile device, so will usually seem “quicker”. From your description it seems there was some kind of network issue on mobile, causing slowness of cache filling. Hard to be sure though.

FYI just because two tracks are from the same album doesn’t mean they will be the “same” artwork - music services often use crazy urls for art tied to the track id, not the album, so although they look the same and are probably the same file on the server, may well be exposed as a different url to clients.

Actually (note for moderator), the answer above may not be entirely correct as far as the particular issue - so not sure it should be labelled “answer”).  This issue kept re-occurring.  I would then load the PC version of the Sonos App, watch it re-populate, and then it would re-populate in the iPhone app immediately as it populated on the PC version of the app.  This was always a fix (temporarily).  So this morning I simply deleted and re-added to Sonos (on my phone) the songs/albums that were having the issue (it was generally the same ones).   So far all is well.  But we’ll see if this is a permanent fix.  

What is weird though, is why would the same art show within a list (like a playlist) on the iphone app, but not on the main “favorites” screen?

My experience is similar on S2. Album art can take a while to populate, and when it does it may show the correct art in the queue but the now playing screen may show no art , or the art from the previous song in the queue ( it has sometimes being correct then reverted back to the previous songs artwork )

This is only a recent problem but not sure if S2 related or due to recently removing my wired bridge and going Wi-Fi only ( though my mesh network is very reliable but not sure if the loss of the bridge is more a factor than the S2 upgrade) 

 NB- all my music is on a Local NAS and artwork is fine in iTunes and as it’s correct in the queue I’m assuming all the bits are in the right place. 

controlav is the author of several third party apps for use in controlling Sonos. While I suspect he doesn’t have access to the Sonos code base directly, I feel fairly confident that he knows what he is talking about. 

I recall the controller can request art in different sizes, depending on where it is to be displayed. On the PC app there were really only two sizes: little ones in the list view, and the bigger one on Now Playing. The Favorites screen likely prefers a larger graphic than the playlist list view, which may effect the fetch of the art and its caching on the device.

(My own apps only ever grab the default size no matter what, because I like a simple life and bandwidth is cheap these days).

My point is, he may be factually correct in what he stated, but those facts are not an “answer” to the question posed.  As the dilemma still exists and does not appear to be slowness (cache related) - as it will stay that way forever on the iPhone unless/until I either open the PC app and go to favorites therein, or remove/re-add the music in question.  Nor does it explain why the same album art shows on some lists within the Sonos app, but not others (the issue seeming to be primarily with the main favorites screen).   I understood the “answer” tag to mean the issue has been resolved, and didn’t want people reading this thread to think the issue no longer existed.  

Who marked my reply as an Answer anyway?

I see the issue happening with both the album (large size art), as well as the small art (such as the songs) - both different sections of the favorites screen.   Incidentally, the issue occurs only with particular albums/songs, even after re-downloaded, etc.   So perhaps there is some sort of error in the graphic/code on the Amazon Music side (which is where the music in question comes from).  Although it seems odd that it will work initially, and then stop after a period of time, as well as appear in some places but not others (same size).

And as far as I can tell, SonosNet looks fairly clean (colors are as represented - green and yellow where indicated)):

It appears that the moderators have removed the ‘answered’ tag. Although honestly, I suspect most people don’t pay attention to that flag, and just look at any unread responses in a thread. At least, that’s the way I treat the forum. 

Odd artwork behavior is usually related to communication issues. As a track is added to a list, a request is entered for its artwork, but there is a time limit. Without a time limit the whole system could stall if there are excessive delays. If there is a timeout, default artwork will be inserted. The communication issues are likely random. Therefore the timeouts will be random and the insertion of default artwork will be random too. Successive runs with the same tracks might result in different artwork populations.

If it was random communications issues, wouldn’t it impact different art/music files?   It seems to be the same culprits (same music files) that don’t populate (it doesn’t happen to random music files).  Also, it still seems odd that the same problematic album art does populate on my phone the instant I open favorites on the Sonos PC app (what is this weird connection between the PC app and iPhone Sonos App)?.   And, why would the album art show up in some places on the iPhone (but not other places), for the same music file? 

On a hunch, make sure that you are in a location with a solid wireless connection for the phone, then change the playlist. I’m not sure exactly what I would want to do, but loading all tracks into the Queue, then saving the Queue using a new name would be a start, Is the artwork under the new name correct? Another approach would be to load the playlist into the Queue, make a small edit at the top of the Queue, and save the Queue as the same or new Playlist.

Shortly after these trials submit a diagnostic if things don’t work out. Post the diagnostic confirmation number here and SONOS Staff can check to see if any issues are logged.

I wonder if there is some share/permissions issue on my PC that could slow this down - and thus cause the caching issue and thus art to not show?   I reinstalled the Sonos PC App, and re-setup my music library link on the PC app.  I noticed that I could not set up the same link on the iPhone Sonos app manually without first doing it on the PC App (it pulled in the music library path ONLY after the Sonos PC app music library path was set up).   If I tried to do it manually on the iPhone, it would say it couldn’t find my computer name (even though I was using the exact same path that it would automatically put in there (apparently pulled from the PC app).   So clearly there is some connection with the Sonos PC app and the iphone App.  And I believe that connection is somehow impacting the art showing.   If I didn’t use the Sonos PC app to set up my music library, I would not have been able to set up the music library on my iPhone Sonos App at all (which doesn't seem to make sense).   Any insight there?

Additionally, is it normal to page down on the iPhone Sonos app and see album art populate as you go ?  In other words - it isn’t already there, but only appears when you are on that part of the screen. It seems to me, that it should be faster than that, and not just populate as you bring the file into view.  True/false?

The PC controller can deal with file permissions for tracks stored on the PC, the phone cannot change permissions for PC files. (If the phone could change file permissions on the PC, there would essentially be no security on the PC)

The controllers don’t store any music, artwork, or the library index. Artwork is fetched from the library as needed. There is a relatively small artwork cache, we do not know exactly how large and the size will likely change from release to release. If the required artwork is in the cache, scrolling will be smooth and successfully fetched artwork will be displayed promptly. Track meta data (Track title, Album name, Artist, etc.) is stored in the index and can usually be fetched promptly from a player. Artwork is stored only in the library. If artwork is required, the player must fetch the artwork from the library and send the artwork to the controller. Artwork fetches are scheduled, music has priority. And as I mentioned in a previous post there is a timeout for artwork fetch attempts. I have noticed that artwork does not always populate in order from the list top to list bottom.

There are a number of asynchronous real time tasks running on the controller, players, and computer. Music data must have the highest priority, artwork fetch has the lowest priority and artwork fetch can sometimes be out of order.