Server Version#: 1.41.8.9834 Player Version#: 1.109.0.329-ea562b95 My subtitles aren’t auto-syncing. It used to work a long time ago, but now it’s not. Doing “Analyze” on any episode/movie finishes very quickly (under a second) and voice analysis doesn’t seem to work. All players have “Auto Sync S…

Is /tmp supposed to be the transcoding directory? Because I have the default /transcode for that and thats mounted to the host. I also quickly tried mounting /tmp on the host and that also didnt help.

[image] Fuechslein: Is /tmp supposed to be the transcoding directory? No. But it’s the location where the various analysis features are storing the decoded audio (in WAV format) before it is handed over to the actual analysation code. If it is not defined in the container, /dev/shm is used in…

[image] OttoKerner: Another common source of analysis failing is insufficient memory in the OS kernel’s inode tables: Linux Tips - #9 by ChuckPa (IIRC in the case of Docker, it’s the kernel of the host OS) Just checked and I am only around 4000 folders, so nowhere close to the limit. root@T…

Voice activity detection does use the location you have “Transcoder temporary directory” set to as its temporary storage. For my own container, using the official Plex image, I have /trancode set as mine. Here’s a relevant VAD taking place (note the last path in the command, /transcode/Transcode/D…

I am using the official Plex image that you linked and no built in version/app of truenas. Just double checked and transcoding works as intended. I can see the temp files in the mapped folder on the host during the transcoding session. The files don’t ever seem to make it there for VAD though. I am…

How do you have this setting configured: Settings -> [Select Server] -> Library -> Generate voice activity data This determines when VAD is triggered. You can’t manually trigger it via the “Analyze” function of a library. If you want to trigger VAD, then either Plex Dance some media (assuming yo…

[image] pshanew: You can’t manually trigger it via the “Analyze” function of a library. You can trigger it manually, if you “analyze” a single movie/episode.

[image] pshanew: How do you have this setting configured: [image] [image] OttoKerner: You can trigger it manually, if you “analyze” a single movie/episode. That’s what I have been doing to test and to gather the log entries.

Mea culpa. But it does use the transcoder temporary directory, not /tmp.

OK I just made a random observation. If i rename the file on the filesystem after it has been already added to plex, then VAD immediately and successfully runs. No idea what to make of this but I don’t feel like renaming all my media….

Voice activity analysis (for Auto Sync Subtitles) not working

Plex Media Server

pshanew February 11, 2026, 3:33pm 20

Did you try the Plex Dance I mentioned above? This can be done on individual/multiple files, seasons, or entire series.

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Voice activity analysis (for Auto Sync Subtitles) not working

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