# ERROR: \[Transcoder\] Unknown decoder 'aac\_lc'

**URL:** <https://forums.plex.tv/t/error-transcoder-unknown-decoder-aac-lc/763186>\
**Category:** Plex Media Server\
**Tags:** server-linux, playstation, plex-web, player-windows\
**Created:** [December 9, 2021, 3:50am UTC](https://forums.plex.tv/t/error-transcoder-unknown-decoder-aac-lc/763186 "2021-12-09T03:50:15Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![xenago](https://avatars.discourse-cdn.com/v4/letter/x/a183cd/32.png) [@xenago](https://forums.plex.tv/u/xenago)\
**Post date:** [December 9, 2021, 3:50am UTC](https://forums.plex.tv/t/error-transcoder-unknown-decoder-aac-lc/763186/1 "2021-12-09T03:50:16Z")

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Server Version#: Version 1.25.1.5286  
Player Version#: Web, windows desktop ( 1.39.0.2753-d48b8c8b ), others such as PS4

I am using NVENC with a GTX 1660.

I am getting this error when attempting to play a file at \<4mbps transcoding:  
[Transcoder] Unknown decoder ‘aac\_lc’

This problem previously occurred in this now-locked thread:

> [@ERROR - \[Transcoder\] Unknown decoder 'aac\_lc'](https://forums.plex.tv/t/error-transcoder-unknown-decoder-aac-lc/409225/16):
>
> Well I haven’t gotten a response yet from anyone over at the UnRAID forums. But I can show that stopping plex via docker does stop ALL plex processes. EDIT: Well apparently either one of the new web client or server updates must have fixed my issue. I just tried to play back the same troublesome episodes from NODE as before and they all appear to work just fine now!

I have downloaded the [server logs](https://support.plex.tv/articles/200250417-plex-media-server-log-files/) and can provide a [sample file](https://support.plex.tv/articles/201035968-generating-sample-files-from-media/) that triggers this issue as well, please contact me via DM!

Edit: DM received, logs/sample provided.

Edit 2: Solution found, thank you @ChuckPa ! For anyone else with this issue, deleting the libaac\_lc\_decoder.so file in the Application Support/Plex Media Server/Codecs/ directory and restarting the server allows the file to play.

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**Author:** ![system](https://global.discourse-cdn.com/plex/original/3X/2/a/2acb9765406f63293d357b4ec509ec39aa28f2ad.png) [@system](https://forums.plex.tv/u/system)\
**Post date:** [March 9, 2022, 3:50am UTC](https://forums.plex.tv/t/error-transcoder-unknown-decoder-aac-lc/763186/2 "2022-03-09T03:50:31Z")

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