· None of the above quite fits
· None of these quite match
· RoonServer locks up when jumping around in a track that is being streamed to a Sonos device
· Spectrum 400mbit > Amplifi Alien
Adding more info.
The server is running on a M1 Pro MacBook Pro, the network configuration is solid as my airplay and RoonReady devices work with no issue.
Sonos endpoints tested were Sonos Move 2 (single or stereo), Sonos Play (single or stereo), Sonos Roam 2 (single), or Ikea Symfonisk (Pair).
The issue happens via the Android/iOS apps, or through the MacOS App running on the MacBook. It is much more common on the mobile apps.
Issue is reproduced by playing a song to a sonos device, and while the song is playing, seeking around the track with the progress bar. Sometimes this seeks as it should, and sometimes an error occurs where audio stops and the progress bar no longer moves. When this happens, the roon server is locked up. No other zones work, I cannot stop audio on the Sonos zone that is frozen, yet the quality indicator light is lit and the play button is stuck. The only fix is to go to my MacBook and restart the Roon Server from the menu bar.
Note: ARC still works while this happens.
As an aside, I’ve been working around this for a while, and used to just close RoonServer from the menu bar, then open Roon (the frontend).
But as of an update ago, opening Roon frontend doesn’t automatically open RoonServer? I need to show package contents on roon, and go manually run RoonServer. Then it works again. Is this intentional behavior? For years running roon opened the server for me.
Hey @Mike_Stratton,
Thanks for the report! Please reproduce the issue and share the track name, and we’ll take another look.
It could be the case that the ‘launch at startup’ option has accidentally been disabled. If you click the Roon Server jellyfish on your upper right-hand corner macOS taskbar> click ‘Launch at Startup?’ and see if you still have issues opening Roon.
Thanks, Mike!
Launch at startup is checked under that menu.
Just closed the server and opened roon again to confirm, and roon sits on the “waiting for your roon server…” screen
Hey @Mike_Stratton,
Understood - this sounds like a completely different issue from what you’ve initially submitted.
As a next step, I’d first double-check your macOS firewall to see if it may be blocking the connection. The easiest way to test this would be to temporarily disable your macOS firewall, reboot the machine, and see if you’re able to connect normally.
If this proves successful, the next step would be to ensure Roon is listed as a proper exception to your firewall, here is all the info you’ll need for this:
We’ll be monitoring for your reply, thanks Mike! 
Hi @Mike_Stratton,
We’re reaching out since we haven’t seen a response in some time but this topic thread never quite reached a conclusion.
Are you still experiencing this problem when you seek during playback on these Sonos devices?
Just to clarify from your earlier report: does this occur when you play to all of the Sonos endpoints individually that you mentioned (the Move 2s, the Plays, the Roam 2, the Symfonisk pair)? As in, the behavior does not only manifest during grouped Zone playback?
Do you have any DSP applied in MUSE when this occurs?
Sonos streaming can be sensitive to playback position changes, particularly in group playback across eras of Sonos firmware, but Roon should handle this gracefully and not freeze. We’re eager to pin down this behavior.
We’ll watch for your reply. Thank you!
Hi, let me listen a bit more later and ill report back when the issue occurs on a song. I’ve learned to avoid seeking so as to prevent restarting the server
This error happens if I go to one zone, or all.
There are DSPs set for every endpoint, however I learned recently that DSP doesn’t take affect when you group sonos zones. So I am guessing the group failures are something else.
Will report back after some testing later.
Just had a roon server lockup trying to play ‘On Track’ by Tame Impala to a pair of Sonos Play at about 5:22. Same symptoms, If i try to play anything, I just see the button change, playback stays at 0:00, and the color quality indicator never goes away,
Not sure if this warrants a new thread.
Due to home renovations my main stereo is packed up. Ive been using a Frankenstein 5.1 setup (stereo move 2s as fronts, stereo plays as rears, a roam 2 as a center, a modified symfonisk to connect a sub mini.
Been listening for a few hours and it seems like roon also gets tripped up if you start modulating the volume a lot on a sonos group. After a bit I started noticing a popping sound from the left move 2, and the indicator light on the speaker would momentarily go orange right after. At that point the volume listed in roon for that stereo pair reset to a low number, but the right move was still playing at the previous volume. Sound would come back about 15-20sec later, but eventually the pop and reset would happen again.
This went on for a bit until the left channel dropped and didn’t come back, and when I started grouping / ungrouping and trying to play songs, the issue of this thread occurred and locked up the server (playback stopped working no matter what I did, even on non sonos zones).
A power cycle of the speaker and reset of the server fixed it. Really not sure how to track that one down, but it was somewhere around 1:20am est.
Mike
One more thing, when the above issue occurred, i opened the Sonos app to see if everything was still connected to the network, and got a bunch of toast messages saying something like roon-291094883719.flac is not encoded correctly and can not be played.
Next time I see it ill get the exact text.
Hey @Mike_Stratton,
Thanks for all the updates and additional information so far.
From a fresh Roon Server diagnostic report, we can see three simultaneous NullReferenceException warnings fire for the left channel of the “Play Stereo” pair, a Sonos Play S58. This is Roon’s UPnP event subscription handler crashing because it received a response from a device that had already been torn down internally; the speaker dropped off the network mid-subscription-renewal cycle.
When the Play Stereo dropped mid-stream, Roon had already delivered a partially written temporary FLAC file to the Sonos HTTP endpoint. The Sonos app, polling this file or receiving it as a queued URI, found it truncated/incomplete and reported it as “not encoded correctly.” This is a side effect, not a cause, the FLAC file was cut off when Roon tore the zone down after losing the device. Nothing wrong with your audio files.
Some next steps for you to consider:
192.168.115.154 is the one that triggered the failure. In your Sonos app, check which physical speaker that IP corresponds to, it may consistently be more battery-stressed depending on placement/charging habits.
Thanks, Mike, and I hope the home renovations are coming along smoothly 
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