Unnecessary transcoding (ALAC, others?) on Sonos?



Hi folks, really glad to see the Plex app on Sonos as it solves my two biggest gripes with the Sonos library support - 1) Sort Order tag support and 2) allowing multiple libraries (to sub-divide big collections).

I've got Plex server running on a Synology DS115, which works great from the Sonos library. But from the Plex app for Sonos, it's unable to keep a stream running. Some digging and I figured out that the app must be transcoding (which the little NAS CPU can't keep up with). My files are mostly in Apple Lossless (ALAC) or FLAC, with some in high-bitrate MP3.

The MP3 files play without issue, and with some testing the FLAC files seem to work. ALAC doesn't. All of the above are natively supported by Sonos, so no transcoding is needed - but it appears the app is doing it. I can't tell if FLAC files are being transcoded (since they seem to work and there's no status I can find that says if it's playing MP3 or FLAC).

Can someone confirm that the Sonos Plex app is playing FLAC files without transcoding? As long as that's done natively, I'll convert my ALAC files to FLAC - no problem!



I would like an answer to this too. Anyone know if FLAC is natively supported by this?


So I bought a Sonos and from what I can see Plex isn’t transcoding my ALAC files so I’m not sure why it would have done yours.


Since you can’t see files currently being played on Sonos in PMS it doesn’t seem to be possible to confirm if files are playing as FLAC files, or whether they’re being transcoded.

Any plex employees able to answer this?


I just enabled debugging on PMS. Played FLAC on Sonos. It Direct Plays here …

Reached Decision id=22807 codes=(MDE=1000,Direct play OK.)

Mar 22, 2017 10:43:58.512 DEBUG - Streaming Resource: Reached Decision id=22807 codes=(MDE=1000,Direct play OK.) media=(id=26716 part=(id=26744 decision=direct play protocol=* streams=(Audio=(id=34273 decision= channels=0 rate=0))))

Mar 22, 2017 10:43:58.512 DEBUG - Content-Length of /share/XXXXXX/Music/3 Doors Down/3 Doors Down - Us And The Night (2016)/1 - The Broken.flac is 22549159.


For anyone else ending up finding this post. Another way to see if something is direct playing on Sonos, check the Status page on plex.tv/web.