There has always been both a number limit, and a timeout limit. How large is the playlist? If memory serves, 500 is generally the number, but there’s also size considerations, if the metadata is larger than normal. And if you’re experiencing a little wifi interference , it’s possible that the load process is failing on a time out. 

Probably worth submitting a system diagnostic within 10 minutes of experiencing this problem, and calling 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.

Though the official line maybe the list can only be 500 max, I’ve read about people complaining they used to be able to play the Dutch top 2000 playlist and since a couple of months are no longer able to.

Could be a change on the Spotify side.

There is a 10 second timeout for loading any playlist, as well as any size limits imposed by the service itself. If something has slowed down the network connection between the service and a particular speaker (the Coordinator in the group specifically), that could explain why a playlist that used to load ok suddenly does not.

Next time it fails, time it from start to error. If it is 10 seconds, that’s the problem.

Hi everyone, although I’ve had a number of Sonos speakers for years now, this is my first time posting in the Sonos Community. I’ve been searching around on here lately precisely because of this problem. My main “playlist” of liked songs on Spotify is somewhere around 1800 songs long now. I didn’t have problems putting this entire list in the Sonos queue for the first couple of years that I was a Spotify subscriber, but I have been consistently encountering the “Unable to add songs to the queue” error for the past couple of months. The problem seemed a bit gradual, in that I could get Sonos to load up the long list to the queue after a few tries, but now it won’t work at all.

I worked with Sonos support this past week via online chat, and then was told to call in. The first person I spoke with focused on the wifi channel selections automatically made by my Linksys Velop mesh system, and the second phone support person I spoke with simply forwarded the following email to me, detailing the various limitations for various music services. (Note: the size of Spotify playlists does seem to be limited, there is no mention of Apple Music however. Using Airplay and Spotify Direct Control are suggested as workarounds.)

In the end, though, I don’t really understand why I was able to regularly listen to my entire Spotify library for years, only to encounter problems at the end of this year.

Music Service Limitations

• Amazon Music
  • Only able to add a maximum of 500 tracks to the queue at once
  • Amazon Music Unlimited shows only up to 100 My Music Playlists in the Sonos controller
• Heart of Space
  • 12 hour session limit
• Pandora Radio
  • 4 hour maximum session length
    • Note that thumbs-down ratings and skips will reset the 4 hour counter, while thumbs-up will not.
  • As of Nov 2016, Sonos displays the most recent 94 user stations (alphabetically sorted). The user can continue adding up to 155 more stations, pushing the least-recently-used out of the list we display (which could be from anywhere in the alphabetically sorted list). This will probably change in Kendrick, when Pandora is slated to go SMAPI.
  • 6 skips per station per hour (Not lifted with Pandora One)
  • 12 skips max per day (Pandora One lifts the daily max)
    Note: via testing, Sonos does not have the 12 skip daily max.
  • Pandora Plus and Pandora Premium accounts are meant for individual, non-commercial use. The cost of an individual subscription only covers the costs of one stream of ad-free songs. You can play your account on any supported computer or device you own, however, only one person can listen at a time on your account.
  • A Pandora Premium subscription is required on Sonos when searching for artists, albums, and playlists, otherwise, only songs and stations will return results.
• Rdio
  • Maximum of 3 Sonos Rooms Playing separate concurrent streams
• Soundtrack Player
  • Maximum of 100 Playlists displaying in the Controller
• Rhapsody/Napster
  • Maximum of 3 Sonos Rooms Playing Separate Concurrent Streams
  • Can stream to either Sonos OR Computer/Phone
    (When one is started the other stops)
• SiriusXM
  • Maximum of 1 concurrent stream
  • 4 Hour Max Session Length
• Slacker
  • 6 skips per station per hour (no daily limit)
  • Paid subscription lifts the skip limit
• Soundcloud
  • 100 Tracks per container (e.g. Playlists)
• Spotify
  • Roughly 500 songs per playlist (can be lower)
  • Each account can only be played at a single IP address at any given time
  • Concurrent streams are allowed within the same household
• TuneIn (Internet Radio)
  • As of version 5.4 (Devo), Sonos does not support MPEG 2.5 audio formats (MP3s) that have sample rates of 12 kHz and below. Most of our partners stream above this rate, but there might be some stations on services that do not have alternate streams.
• YouTube Music
  • All containers for uploaded music have a limit of 999 items.

*You can bypass limitations with Airplay or even Direct Control from Spotify

Yeah, and my apologies for the overlong post. But, in short, I feel exactly the same way, and my timeline for this change is pretty much the same as yours. I still don’t know the underlying “why”: i.e. why now, and not before? And is it generally the music services that enforce these limitations, or Sonos? At this point, though, I am pretty much resigned to adapting to workarounds: either doing the work of dividing my large collections into multiple smaller playlists, or using Direct Control/Airplay, etc.

Just strange this seems to have changed recently. Would this be on the Spotify or the Sonos side?

So this must be a Spotify thing.

Based on my debugging I see nothing that indicates issues with anyone’s local network. The 10 second timeout fires because of the time taken for speaker->internet->CDN->spotify and back, and there is little you can do for any of those steps.

So I have been taking a deep look at this issue for the last few weeks, and have made changes to my own Windows app to handle these large playlists. It was frankly trickier than I had expected, but its all working now.

With the “normal” method, the app makes a single call to the Coordinator speaker and hands it the playlist details. The speaker then makes a single call to the music service to get all of the items and adds them to the queue. This all must be completed in less than 10 seconds, which is not possible for Spotify playlists containg 1000 or so items (as both the app->speaker and speaker->service calls are both limited to 10 seconds).

Instead I tried adding them using “pagination” - the app grabs the playlist contents 500 at a time, then adds each item in much smaller chunks to the Coordinator’s queue. This works, but is a LOT slower than the “normal” method. The 1000 item Spotify playlist that I have mostly been testing with takes a couple of minutes to load this way, and frankly I don’t see any way of making that any faster. But it does work. And once it does, you can then immediately create a Sonos playlist of the exact same tracks and use that in future, which loads almost instantly of course.

I have some more testing to do before releasing my updated app, but I am happy the concept works even within the time limits imposed by the Sonos and Spotify implementations.