Server Version#:
Player Version#:
I used to be able to play rips of my 4K Blu-rays with TrueHD audio streams over HDMI ARC from Sony A80J to my Emotiva XMC-2. Now I find that they are only transcoded to two channels by something called Opus. Will this be fixed or is the new way?
I donât think any thing changed in that regard. Does that run our Android TV app? What is the passthrough setting set to?
The audio will transcode, but it should transcode to a 5.1 signal, not 2.0.
In addition to the passthrough setting, what version of Plex Media Server and the Plex Android TV app are you running? You can look in the apps themselves or check Authorized Devices.
Edit: Also check the audio settings on the TV. I think you should have Speakers = Audio System and Passthrough = Auto. Iâm using this YouTube video as a reference. The TV audio settings are covered ~5 minutes into the video.
The tech specs for the XMC-2 list HDMI-ARC, not HDMI-eARC (link).
HDMI-ARC cannot pass TrueHD or dts-HD audio due to bandwidth constraints. It is limited to AC3/EAC3/DTS/PCM 5.1 or less, including EAC3+Atmos.
It is a moot point given the HDMI-ARC limitation, but no known TV supports passthrough for TrueHD audio from TV based apps. Even if the TV & Emotiva were connected via HDMI-eARC, TrueHD audio would still transcode.
I just tested with a different system in my house. Marantz 1609 from Google TV on Hisense 50H8G. Same result of Opus downcoverting to 2.0.
Before all this, I was getting 7.1 passed to XMC-2 via TrueHD audio stream from ripped 4K Blu-ray with no transcoding. Now these downconvert to 2.0. I have to fall back to the secondary plain DD 5.1 stream to avoid transcoding to get direct play on audio and video which is my default preferred method.
I also get Dolby Atmos, etc to the XMC-2 via apps like Disney and Apple.
I am using the very latest build of Plex server and Plex client apps.
I have checked HDMI passthrough turned on all hardware and in apps.
My point to all this is I was not transcoding even when sending TrueHD before. Now everything that isnât bog standard DD 5.1 is downconverted. What Changed? I guess itâs this Opus thing I read about?
Looks like there is a known issue around that. I canât tell if it was related to when transcoding to opus was introduced. To get 5.1 the only workaround right now is to change the passthrough option to Optical and enable AC3 and DTS, which isnât great but better than 2.0
I know that TrueHD was passing in some configuration without transcoding because I tested it. I would not have adopted TrueHD for my rips otherwise. I have set up my rips to conform to what I know will work since I do not want to transcode. Normally, DD 5.1 or EAC3. Now that TrueHD down converting is broken for me, I am having to redo my rips and this time I will include TrueHD and the DD 5.1 so I will not be caught off guard again.
Plex should do a better job of alerting their lifetime members when they arbitrarily change something like this. Itâs pretty user hostile.
1 Like
If your TV is connected via HDMI-ARC then it never passed TrueHD (or dts-HD) audio. HDMI-ARC supports AC3/EAC3/DTS/PCM at 5.1 channels or less (EAC3 5.1 + Atmos is supported).
Even if it was using HDMI-eARC, TrueHD from TV based apps would still not pass, as TV manufacturers block it (most support TrueHD passthrough for HDMI attached devices, just not from TV based apps).
If you want TrueHD + Atmos audio and 4K HDR / Dolby Vision, youâll need to acquire a Nvidia Shield Pro or Xbox One (I do not know if Xbox supports DV). They are the only streaming devices that passthrough TrueHD + Atmos audio. Plex for Windows or Plex HTPC on Windows will pass TrueHD + Atmos audio, but the video is tonemapped by the app to SDR.
Ideally, you would connect it directly to your audio equipment, taking the TV out of the equation for audio. For example: Shield â HDMI â XMC-2 â HDMI â Sony TV.
See [INFO] Plex, 4k, transcoding, and you - aka the rules of 4k for additional information.
Regarding Plex transcoding TrueHD to stereo, that should definitely not happen. You should get 5.1 audio over HDMI-ARC. Hopefully Plex can fix whatever is happening with the Android TV app in short order (the issue BigWheel mentions).
I have a Sony X85J with Google TV (the new Android TV) and itâs connected to a Sony HT-X8500 via eARC.
TrueHD plays fine without transcoding on Jellyfin and even tested playing it on VLC via network share.
Plex, however, insists on transcoding it to Opus with the reason âTrueHD audio is not supported by the deviceâ even though it seems my TV and soundbar do support it.
1 Like
Just wanted to throw my 2 cents in and say that Iâm getting the same issue. My Chromecast with Google TV is plugged into my Denon Receiver and was previously able to passthrough TrueHD audio from my Plex collection. Now, the stream fails saying that there isnât enough bandwidth to transmit both the 4k HDR video stream and the TrueHD audio stream so I fall back to the DD 5.1 stream. I went through every setting and everything is set to passthrough. Just odd that it stopped working all of the sudden.
1 Like
It seems like TrueHD is no longer transcoding to Opus and is instead transcoding to EAC3, but itâs still transcoding when it shouldnât. As I said in my previous post on this thread, my TV and Soundbar both support TrueHD and similar software such as Jellyfin plays it fine without transcoding, and even playing via network share in VLC (for Android TV) works fine. Hopefully this can be looked into.
I now have a Emotva MC-1 processor that supports EARC hooked up to my Sony A80J running Google TV. Just tested again and my TrueHD streams are down converted to 2.0 audio. If Jellyfin and VLC can figure this out whatâs wrong with Plex? Whatâs the delay. Iâm a lifetime Plex member. I paid so these types of things work?
jellyfin/vlc may be decoding to PCM to the tv (may show as direct play on dashboard, but not truehd on receiver/soundbar).
No known smart tvs will pass through truehd, other than by external HDMI device (like shield/xbox) via E-ARC (not regular ARC), until someone can prove otherwise.
1 Like
Okay if you are the expert. But what about the down convert to 2.0 audio. That is still happening? Where is the fix for that?
This is the way 
@ctbarker32 - Genuinely, there is absolutely no TV on the market right now that will pass TrueHD or DTS-HD over HDMI via the internal apps, regardless of ARC / eARC status. This is an indisputable factâŠ
You may well have experienced all sorts of behavior, however none of them would have been âDirect Playâ of those audio tracks. It is simply not possible. Cannot happen!
The ONLY way to get TrueHD and DTS-HD to pass through HDMI is via an external player that is connected via HDMI, either directly to your processor or through a TV that supports eARC, which is also connected to a processor / AVR that also supports eARC.
Ideally, TrueHD should be transcoded to a supported 5.1 or 7.1 format. However, there are many things that could influence Plexâs transcoding choice, including TV settings, Plex Android TV app settings, and Emotiva MC1 settings.
What version of the Plex Android TV app is on the Sony?
Update to the latest available version, 8.29.1 or 8.30.0 if you are receiving beta releases.
In the Plex Android TV app:
- Set passthrough = HDMI
- Enable network logging
- Note the URL to retrieve logs in the lower right corner of the settings screen
Play a video with Dolby Digital (AC3) 5.1 audio for 15 - 20 seconds. Does the MC-1 indicate it is receiving Dolby Digital audio?
Play a video with TrueHD audio for 15 - 20 seconds. What is displayed on the MC-1 front panel during playback?
Stop playback. Do not exit the Plex Android TV app.
Retrieve the Plex Android TV app logs (Retrieving Android TV Logs).
- Go to http://tv_ip_address:32500/logging (the URL in the corner of the settings screen)
- Save the web page as a text file and attach it to the thread. Drag it into the message window. It will attach at the cursor location.
Retrieve the Plex Server Logs via Settings â Server_Name â Troubleshooting. Attach the entire ZIP file to the thread.
1 Like
This topic was automatically closed 90 days after the last reply. New replies are no longer allowed.
