Server Version#: 1.32.8.7639 (SYNOLGOY DS920+ DSM 7.2.1-69057 Update 3)
Player Version#: SONOS App 11.12
Out of the blue, none of the SONOS apps can browse my Plex Music Library. I have SONOS S1 and S2 devices and use the app on IOS, iPadOS, MacOS, and Win11.
I did move my Music library to another Volume on my Synology, removed the original Music library, and added the moved library. This created new entries in the database of the PMS.
After some Googling and confirming that all network-related topics are correctly implemented - which they were as the SONOS speakers happily play Plex-hosted music if referred to directly in the SONOS App - I did some digging in what happens between Plex and SONOS.
If my understanding is correct, the control channel between SONOS and Plex happens over the Internet, while streaming happens directly between the PMS and the SONOS speakers.
When using the SONOS app, I see outgoing requests to sonos.plex.tv, and when looking into the console output of the PMS I can see incoming requests pointing to the actions I’m doing on the SONOS App.
Example: looking for an Artist with “billie” in the name resulted in:
Jan 07, 2024 11:53:10.909 [139925960825656] DEBUG - Request: [34.244.153.183:55404 (WAN)] GET /hubs/search?query=billie&limit=50&timeout=2500 (7 live) #12e138 TLS Signed-in Token (TRippled0t) (Plex for Sonos)
Jan 07, 2024 11:53:10.996 [139926185143096] DEBUG - Completed: [34.244.153.183:55404] 200 GET /hubs/search?query=billie&limit=50&timeout=2500 (7 live) #12e138 TLS 87ms 53671 bytes
It looks like the App then asked for a photo. Note: all IP addresses in the request are AWS IP addresses. Looks like the entire app stack is protected by Cloudflare and developed on AWS.
Code 200 is HTTP-speak for “OK”.
Code 404 is “Page not Found”.
Jan 07, 2024 11:53:11.677 [139925960825656] DEBUG - Request: [34.242.26.79:47472 (WAN)] GET /photo/:/transcode?height=1&minSize=1&upscale=1&url=%2Flibrary%2Fmetadata%2F17855%2Fthumb%2F1704548424&width=300 (7 live) #12e13c TLS GZIP Signed-in Token (TRippled0t) (Plex for Sonos)
Jan 07, 2024 11:53:11.677 [139925960825656] DEBUG - [Req#12e13c] Photo transcoder: Request for url [/library/metadata/17855/thumb/1704548424] (is local: 1 upscaled: 1)
Jan 07, 2024 11:53:11.828 [139926185143096] DEBUG - Completed: [34.242.26.79:47472] 200 GET /photo/:/transcode?height=1&minSize=1&upscale=1&url=%2Flibrary%2Fmetadata%2F17855%2Fthumb%2F1704548424&width=300 (7 live) #12e13c TLS GZIP 150ms 11226 bytes
This worked, as I noticed a picture in the search results in the SONOS App.
Then when tapping on the search result, I get the “Unable to browse” message.
It looks like it initially got some metadata:
Jan 07, 2024 11:53:13.751 [139925960825656] DEBUG - Request: [63.32.107.51:12048 (WAN)] GET /library/metadata/17855?includePopularLeaves=1 (7 live) #12e141 TLS Signed-in Token (TRippled0t) (Plex for Sonos)
Jan 07, 2024 11:53:13.759 [139926185143096] DEBUG - Completed: [63.32.107.51:12048] 200 GET /library/metadata/17855?includePopularLeaves=1 (7 live) #12e141 TLS 8ms 15906 bytes
Jan 07, 2024 11:53:13.949 [139925960825656] DEBUG - Request: [63.32.107.51:48431 (WAN)] GET /library/sections//all?type=9&artist.id=17855&sort=originallyAvailableAt:desc (7 live) #12e143 TLS Signed-in Token (TRippled0t) (Plex for Sonos)
Jan 07, 2024 11:53:13.950 [139926187252536] DEBUG - Completed: [63.32.107.51:48431] 404 GET /library/sections//all?type=9&artist.id=17855&sort=originallyAvailableAt:desc (7 live) #12e143 TLS 0ms 259 bytes
Here it goes wrong and the PMS returns a Page not Found error, which is then translated in the SONOS App as “Unable to browse”.
I tried to mimic the request using a browser, but evidently, without understanding the session-authentication mechanism I cannot invoke these URLs (error 401).
I initially thought this might be related to caching issues. But it’s unclear how to clear the PMS cache on a Synology and I’m not going to delete the entire cache directory without understanding what that entails.
But it could also be something else. Unfortunately, I cannot find the web service and its files on my Synology to verify if that URL exists.
Any help from Plex support would greatly be appreciated. I think I’m quite close to understanding where the issue resides, not necessarily how it occurs.
KR, Dirk
