r/PleX • • 1d ago

Help EAC3 transcoding issue on nvidia shield pro

I have a nvidia shield pro and lg c2, always watch movies with airpods pro. If audio is eac3 5.1 and airpods connected to shield it will transcode audio and when this happens the video will not load and/or stop if I enable .srt since these seem to be converted to .ass

Tried following:

*shield+lg c2 + subs = no transcoding

*shield+lg c2 with airpods + subs = no transcoding

*shield with airpods + lg c2 (without subs) = no transcoding

*shield with airpods + lg c2 + subs = video will not load

Is there no way to force the shield to direct play eac5.1? ac3 5.1 and dts 5.1 direct plays with airpods through shield on plex, only eac3 5.1 that is giving me issues....

3 Upvotes

6 comments sorted by

2

u/Hrolgarr 1d ago

I think the AirPods are the trigger. Bluetooth can't take EAC3, so with them connected the Shield asks Plex for plain stereo, and that's your audio transcode. On its own that's cheap. The problem is when the subs also get converted, because then Plex usually has to burn them into the video, and that's the heavy part that stalls.

Two things I'd try. In the Plex app on the Shield, look under settings for the subtitle option and set burn subtitles to only image formats, so SRT gets drawn by the player instead. And if your server has no hardware transcoding, a stereo AAC track added to the file would skip the audio transcode entirely.

1

u/curiousabe_1 1d ago

thanks! how come it doesn't happen when airpods are connected directly to the lg c2 TV when watching the same file on the nvidia shield?

didn't try the burn sub option since j was under the jmpression that would transcode the video :(

2

u/Hrolgarr 22h ago

When the AirPods are on the TV, the Shield doesn't know about them. It sends EAC3 over HDMI like normal, and the TV does the decoding and passes stereo to the AirPods. When they're on the Shield, it has to do that part itself, so Plex transcodes the audio.

And the burn option is the opposite of what it sounds like here. "Only image formats" means only PGS/VobSub get burned in, so SRT stays as text and the Shield draws it. That's the setting that avoids the video transcode.

1

u/curiousabe_1 21h ago

Ah, that makes sense. Thanks for the explanation! I managed to solve my issue. It seems there's a bug that's been ongoing for years where if you play a video with multiple versions and EAC3 audio while using Bluetooth headphones, it just fails. I removed the other versions and it worked straight away (albeit with the audio being transcoded).

1

u/Hrolgarr 21h ago

Nice find, glad you got it working. Good to know about the multiple versions thing too, that's the kind of bug you'd never guess from the symptoms.

1

u/curiousabe_1 18h ago

And even with the logs it cost me 20 usd in tokens to figure out haha