Can transcoding through HDMI controlled as my receiver does not have DTS support and plex does not take that into account and I get stereo. For that I have to set it to optical pass through and select AC3 as there is no option to select encoding in HDMI mode
Tried beta, does not fix anything. Stereo opus audio on HDMI as well as optical atleast for me, even the DTS audio is not transcoded to Ac3 on optical, it stays on DTS , DTS is unselected though
Would you be able to grab the logs from your device for me? Steps for fetching them are available here; Android, Android TV, Fire TV, Portal Logs | Plex Support
Apologies for sharing misleading post yesterday. I was still on stable where it said beta in playstore, updated correctly to beta now and sent you client log in personal message.
Scenario 1: playing Tru HD file(saying truHD not supported), transcoded to opus over HDMI, getting dialogues from all the channels
Scenario 1A: changing pass through to optical in plex app setting, only AC3 is selected in optical, now tru HD is transcoded to AC3(not in logs shared by me)
Scenario 2: playing DTS over HDMI pass through, says DTS not supported but copies DTS only.
Scenario 3 changing pass through to optical in plex app setting, now DTS transcoded to 5.1 AC3 when only AC3 is selected in optical
Please note physical connection between TV and AV is not changed, still connected Via HDMI only in all the scenarios above
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This seems like it’s working correctly, unless I’m misunderstanding something. Since your setup doesn’t support TrueHD, we transcode to Opus (this is a faster transcode so uses less resources on your server). DTS isn’t supported, but since you use HDMI passthrough we can playback DTS core with 5.1 channels over PCM, switching to optical would force things to use AC3 instead of PCM or Opus in order to keep 5.1 channels playing.
My setup only supports DDP and DD, so when it was transcoding to EAC3 over HDMI everything was fine, but now on OPUS, I get same audio from all speakers, same is the case with DTS, it copies the same audio feed instead of transcoding( this was the problem even before OPUS change was made). I am not sure how to get EAC3 over HDMI in case the audio codec is not supported as there is no option for selecting the preferred transcoding in HDMI. I never get 5.1 audio over PCM but stereo
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What are you referring to with DDP and DD? What AVR or soundbar are you using? It’s odd that you are seeing stereo playback of PCM audio, they should be delivered to you in 5.1 still - unless your Android device is configured for only stereo output.
DDP=Dolby Digital Plus
DD=Dolby Digital
I have set audio passthrough to Auto in Tv settings. I use zebronics 9400 pro. If it’s not in dolby audio, it plays everything as stereo and that too with very low volume. So I am suspecting TV is doing the processing in case of OPUS or DTS, If an option could be provided to choose transcoding in HDMI pass through, it will solve the purpose as users will be able to chose the transcoding just like optical
My TV is set on auto for audio output but even if I choose dolby digital plus in TV settings, Plex does the transcoding in opus
and this is what I found on Samsung site. that PCM will always be 2.0
Also, according to the table provided here in the article below, ARC cannot do uncompressed 5.1. Isn’t 5.1 PCM an uncompressed format?
Ah EAC3 and AC3, should of realised that 
If its via ARC and not eARC then it would only be PCM stereo as you’ve pointed out.
Just so we’re on the same page, what changed when we introduced OPUS transcoding support, did we start to transcode into OPUS instead of AC3 / EAC3?
Having selectable codecs for HDMI wouldn’t solve your particular issue as OPUS isn’t supported over HDMI and would always be delivered as PCM - for PCM we can’t determine what the channel limit would be when it’s played on the device. We probably need a new passthrough option for HDMI (ARC), or a setting that indicates your setup only supports PCM with 2 channels. Will discuss with the team and see what we can do.
For now, it sounds like your best option is to enable optical and select AC3, this would allow you to use AC3 passthrough and mimic the previous behaviour.
Just so we’re on the same page, what changed when we introduced OPUS transcoding support, did we start to transcode into OPUS instead of AC3 / EAC3?
Yes it transcodes to OPUS and nothing else.
Glad I was able to explain myself.
When I said give an option to user to select transcoding, I meant an option just like its available for optical where one can select which codec it should be transcoded to incase its not natively supported… Right now it only transcodes to OPUS, if a way to provide check boxes against the codecs or a preference order option where I can put EAC3 on top followed by AC3 and then DTS and then OPUS/PCM etc. This way Users can set their preference of transcoding according to their hardware.
Then for the time being let me revert to 8.23.1 and wait for good news when we have a new development on this. At least that way I will have EAC3 transcode support over HDMI
Plex for Android 8.25.0.28514-beta
Fixed it for me.
There are systems that support AC3 and EAC3 but not 5.1 PCM.
I have a few streaming devices. The FireTV + Echo Studio supports AC3 + EAC3 but not 5.1 PCM. Prior to this new update TrueHD was transcoded to EAC3 which works fine with FireTV + Echo Studio. But if TrueHD is transcoded to Opus 5.1 and then passed to the Studio as PCM 5.1, I will only get a stereo downmix.
If I do as you suggest and set passthrough to optical on the FireTV+Studio, TrueHD would transcode to AC3 but I would lose the extra quality of an EAC3 transcode. Additionally, I would have to change passthrough back to HDMI everytime I played a movie with EAC3 to avoid having it transcoded to AC3.
There are receivers and devices that don’t support 5.1PCM other than optical in only receivers. I think this is what @VicksJ is also describing.
I sort of understand that Plex wants to keep things simple on the user end and not let us pick our transcode targets ourselves. But you are either going to have to program in a lot of conditions, or just disregard Plex users who don’t have more typical setups.
The FireTV+Studio also does not support AAC5.1. I wish I could select EAC3 as a transcode Target to keep multichannels. Right now I have to keep turning on optical passthrough whenever I want to force AC3 just to keep 5.1. It’s a bad user experience that could easily be fixed with more flexibility on the user end
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Yes that’s exactly my situation currently, previously I would have to change to optical AC3 option in case of DTS5.1 AND AAC5.1 to transcode to AC3 as there is no option to force EAC3 in HDMI, but now for every transcoding if audio is not in EAC3/AC3 have to use optical AC3 and then switch back to HDMI in case I have to play EAC3 natively. So had to toggle between HDMI and optical previously as well but more now. And if I don’t toggle, I loose EAC3 benefits as you suggested
I think the most ironic thing is that the andriod phone app has these audio targets and the option to select them as pass through targets while the andriod TV app does not… it seems that this really should be the other way round and would probably solve ALOT of these complaints!
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We’re not disregarding anyone, hence my replies 
I want to find the right solution that works for everyone.
This is why it becomes complicated, these codecs are what the device supports and not what is supported on passthrough.
The reason it’s not supported on TV is because we need a big refactor in order to make this work correctly, before Opus support it was picking EAC3 or AC3 for Dolby codecs mostly by mistake.
Previously was AAC 5.1 and DTS 5.1 being transcoded to AC3 as well? 
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Only via Optical AC3 selection and not through HDMI. So if a solution can be provided for that as well to force EAC3/AC3 transcoding of DTS/AAC via HDMI that would be awesome and no more toggling between HDMI and optical
Hello! Just confirming the latest beta did fix this issue for me with Plex on Google TV. Prior to the beta it was transcoding to OPUS and not working with my SONOS setup. Now, the beta is correctly converting everything to AC3. Thanks!
I think we need the Android tv/Nvidia Shield app like this, but more broken down. I am a Sonos user who can only use AC3 / DD and when changes like this are made, it affects the many Sonos users out there. For instance, under the audio settings:
Choose HDMI ARC, EARC, or Optical Passthrough and then have subcategories of all of the formats you can choose manually, that the device supports. Similar to how the optical one is now or how in Nvidia Shield you can choose manually all of the various audio formats you can (or want to) use.
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Yeap, this would be the ideal solution… but it’s a known for how many years now, I don’t expect the andriod TV app will be updated anything soon.
