Opus files incorrectly transcode part way through tracks after update to Emby for LG 1.0.51

[magickii 2]

After updating to Emby for LG 1.0.51, I started noticing that Opus audio files are always transcoded, even on a local connection, but the transcoding starts the stream offset about ~30s into each track.
So far I have only observed this issue on Emby for LG 1.0.51, all other local clients are able to Direct Play.

I'm aware that LG and Opus have inconsistent support across models.
I cannot confirm if Emby for LG was able to Direct Play these Opus files prior to the app upgrade, but hopefully if it were I would have noticed issues with playback sooner.
The LG TV is an OLED C4 on webOS24 (9.2.2-1806)

I did not immediately see anything in the embyserver.txt log that might indicate an issue, but one of the tracks that had issue started at 2026-09-25 19:03:12.978 and I have attached that track's ffmpeg-transcode log as well.

On the server side, I have observed this behavior first on 4.9.5.0, and it has continued after upgrade to 4.10.0.40

 

embyserver.txt ffmpeg-transcode-69497d66-a0cd-4731-9262-96366405f79b_1.txt

[Abobader 3544]

Hello magickii,

** This is an auto reply **

Please wait for someone from staff support or our members to reply to you.

It's recommended to provide more info, as it explain in this thread:

Thank you.

Emby Team

[Luke 43549]

Hi, there’s no evidence it switched, in fact, we don’t even have a switching mechanism for audio like we do for video.

 However with this update I think we did stop direct playing opus due to all the problems reported with it. @SamES can confirm.

[magickii 2]

Thanks for the quick reply. I have two questions in the meantime,
1. Is there a way that I can force opus to Direct Play a specific track to help debug if my particular model has issues playing opus?
2. Why might the transcoded tracks be starting part way through rather than at the beginning, and is there any additional information I can provide to help with debugging that?   @SamES

[Luke 43549]

Quote

Is there a way that I can force opus to Direct Play a specific track to help debug if my particular model has issues playing opus?

A specific track, no, but you can temporarily restrict user transcoding permissions to see what happens when it is forced to direct play. Just make sure to remember to undo it afterwards.

[magickii 2]

On 9/28/2026 at 2:24 PM, Luke said:

you can temporarily restrict user transcoding permissions to see what happens when it is forced to direct play

Ok, had a chance to test this. It appears when I disable "Allow audio transcoding to a compatible format, if necessary, during media playback" for a user and try to play an opus track then the Emby for LG app just shows a loading spinner indefinitely and does not play (or change to the Now Playing view).

[Luke 43549]

1 hour ago, magickii said:

Ok, had a chance to test this. It appears when I disable "Allow audio transcoding to a compatible format, if necessary, during media playback" for a user and try to play an opus track then the Emby for LG app just shows a loading spinner indefinitely and does not play (or change to the Now Playing view).

That signals to me that the LG player isn't handling it, although I'm surprised you're not getting an error message.

[magickii 2]

Same. It seems Opus has always been transcoded to this TV.
It made me curious so I tried to play both Opus and Vorbis through the stock LG Music app too and both file types threw errors that they were not supported, even though I was fairly certain at least Vorbis was officially supported for webOS24.

[Luke 43549]

It’s possible that they are supported in some fashion. But they don’t publish those details beyond just saying that a certain format is supported.

[magickii 2]

Indeed. Good to know, and I guess it leads us back to the original problem.
If there's any logs or ffmpeg calls I can run to help debug the transcoding start time offset, let me know.

[Luke 43549]

@SamES

[SamES 1143]

On 27/09/2026 at 09:56, magickii said:

Thanks for the quick reply. I have two questions in the meantime,
1. Is there a way that I can force opus to Direct Play a specific track to help debug if my particular model has issues playing opus?
2. Why might the transcoded tracks be starting part way through rather than at the beginning, and is there any additional information I can provide to help with debugging that?   @SamES

As you have noted, OPUS playback is inconsistent across LG models, and even on supported models playback isn't always reliable.  This is why we disabled it for DirectPlay, and even your test by disabling "Allow audio transcoding to a compatible format, if necessary, during media playback"  confirms this, which is the right way to test this.

As to why it is starting part way through, that sounds like an issue with the transcoding process. I don't see anything of concern in the transcoding log from your earlier post. Does this occur with all Opus audio files, or just some? It could be an issue with the way the file has been encoded?

You can send me a file via PM which I can test on a few of my devices to see if I can reproduce.

[magickii 2]

On 10/4/2026 at 7:35 AM, SamES said:

Does this occur with all Opus audio files, or just some? It could be an issue with the way the file has been encoded?

So far, yes, it's been all Opus files I've checked. In total I've got roughly a dozen albums that I've noticed it on.
It's still possible something odd is up with all of their encoding, the files were converted with opusenc from FLAC---just the defaults though, `opusenc "${src}.flac" "${dst}.opus"`---with only spot metadata correction as needed using `opustags`.

$ opusenc --version                                
opusenc opus-tools 0.2 (using libopus 1.6)
Copyright (C) 2008-2018 Xiph.Org Foundation

I'll get a source and encoded file sent over to you in a moment, thank you   @SamES

[visproduction 379]

Flac and Opus use different lossless compression codecs.  In post production work for film and video, it is typical to convert first to a uncompressed codec and never convert compressed codec to another compressed codec.  Usually, the first response in post, is to ask for a master instead of any compressed copy, even if it is lossless.

I noticed this comment in a post about a similar issue:

https://www.reddit.com/r/musichoarder/comments/12742q7/flac_errors_playable_and_not_playable/

" bad headers? try converting back to .wav, then re-encode - see if that fixes the issue."

This test could show that conversion from Flac to Opus is part of the issue. Another test would be to take any original, uncompressed master and convert it to Opus and see if that plays smoothly.  Unless you test for these, you won't know if the conversion needs adjustment and you could waste time looking elsewhere.  Just an idea.

Edited October 26 by visproduction

[magickii 2]

18 hours ago, visproduction said:

In post production work for film and video

hello as well, from the post-production/m&e world 
I appreciate you offering suggestions.

18 hours ago, visproduction said:

Usually, the first response in post, is to ask for a master instead of any compressed copy, even if it is lossless.

I agree with this in practice professionally, but here its not a given that I have access to any uncompressed or losslessly compressed variants, or even that the track had a source variant.
Once asked for an example file, I offered the source with the converted since I had done the conversion.
While I can actually request WAV from the storefronts of some of the other affected albums, the one I had already uploaded logs for did not offer WAV.

18 hours ago, visproduction said:

This test could show that conversion from Flac to Opus is part of the issue.

This is a reasonable variable to eliminate, even though I think it's unlikely given that the same files play fine with no warnings or errors on a variety of my other devices and clients.
From the data we have, the issue appears only when Emby is transcoding.
I'm not sure if I can force Emby on one of the devices that is successfully Direct Play'ing to instead transcode, but that might also be useful to see.

Nonetheless, I have now tried converting to WAV first with the track I provided, but there is no difference in playback on Emby for LG.
FLAC => WAV => Opus starts from the exact same point in the track as it does in the track without the intermediate WAV conversion.

19 hours ago, visproduction said:

Another test would be to take any original, uncompressed master and convert it to Opus and see if that plays smoothly.

This also has not made a difference on a few tracks I have tried. Emby for LG starts the WAV masters from the beginning, but starts part way through the variants converted to Opus.

[visproduction 379]

Magic.  Great breakdown and testing.  Even after your test conversions, the issue remains and using a different .wav master did not make a difference.  I think it helps to be able to now focus on the Emby conversion as the most likely problem.  Could it also be the LG TV?  I remember finding playback problems often with LG.  Hopefully, your tests has saved time for anyone digging down to fix this.

Edited October 27 by visproduction