Server Version#: 1.30.0.6486 (latest TrueNAS TrueCharts version)
Player Version#: 7.0.23.8111-8c8a6a9b7-Plex
My AV receiver is the Yamaha A6A hooked up to a Roku Ultra 4800R.
I’m playing Plex Atmos and DTS:X demos on my Roku Ultra. It’s configured the audio in Passthrough mode, but Plex keeps transcoding only the audio to EAC3. Video is Original.
These demos playback the audio properly from Windows to my receiver over HDMI from my GPU.
Both Atmos and DTS:X content both work from VUDU and Netflix on the Roku.
I have the one audio option: “Allow DTS-HD” enabled.
Local and remote quality are set to “Original” and Direct Play on “Auto”. Changing it to “Force” doesn’t change anything.
“Allow Direct Stream” is enabled.
Stream Info showing “(EAC3 5.1) - convert” for every Atmos and DTS:X file I tried including DTS-HD audio.
The streams are correctly set to the highest quality audio version.
What can I do to get Plex to pass audio through to my receiver from my Roku Ultra rather than transcoding it?
The Art of Essence demo video did playback in Dolby Atmos with high channels. The only difference is its Dolby Digital Plus rather than Dolby TrueHD.
I think this is a bug in the Roku Plex app.
I actually tested this video for Dolby Vision, and the Dolby Vision playback works. Yet on another demo video, Blocks, Plex refused to play it even when selecting “Force” for Direct Play.
I’m able to play this same demo with the correct colors in Windows on this TV, but it plays in HDR10. Not sure how it works though. It only works in the official Media Player app.
Looked around on some Roku forums. Older Rokus didn’t have support for Dolby TrueHD, so maybe that’s it? Even with passthrough?
That seems weird to me because passthrough is literally pass-through-to-another-device; therefore, it doesn’t matter if the Roku supports it or not which is why my PC can output DTS:X and Dolby Atmos over Dolby TrueHD to my receiver.
Also, my Roku does show Dolby Atmos and DTS:X MA as supported outputs to my receiver. Not sure if that means Dolby Atmos over Dolby Digital Plus or not.
Lastly, it’s possible passthrough doesn’t work as I expect. For instance, my TV supports only Dolby Atmos and not DTS in any shape or form. When using eARC, there’s no way to transmit DTS to the receiver from the TV. This could mean eARC isn’t passthrough or that my LG C1 doesn’t support passthrough.
Roku says it recognizes Dolby Atmos and DTS-HD MA over HDMI for passthrough. It doesn’t specify which Dolby Atmos nor DTS:X.
Even still, DTS-HD MA audio is being transcoded to Dolby Digital Plus. I specifically checked the box for “Allow DTS” and ensured it was checked for all media I tried.
This is a new Plex install from earlier this month.
2 things:
Dolby Atmos over Dolby TrueHD might not be supported, but transcoding should then change it to Dolby Atmos over E-AC-3 (Dolby Digital Plus) to retain Atmos heights.
DTS:X might not be supported, but DTS-HD MA is supported and should be output instead of transcoding to Dolby Digital Plus (a lower-quality format).
I’ve been eyeballing the NVIDIA Shield TV Pro. Found out it’s from 2019. I honestly thought the 2015 model was the only one around, so I thought it was super old. Now that I see there’s one from 2019, I’m wondering what happened to the newer models? HDMI 2.1 is out, and VRR or QMS specifically would be great feature-adds.
At this point, I’ve only been experimenting with Plex because I only have one Blu-ray movie, but I’m hoping to start using it and my first foray was pretty poor so far. I wish I didn’t have to do so much research just to figure out what was going on.
I understand this is Roku’s fault in some ways, but I didn’t know that as a user.
Lastly, what about DTS? Roku supports DTS-HD MA, but even that isn’t being passed through with all the correct settings checked.
The Nvidia Shield Pro will passthrough TrueHD + Atmos and dts:X audio, along with pretty much any other audio format you will find on a DVD or Blu-ray disc.
I’ve the 2015 model connected to a Denon receiver, and it direct plays everything I throw at it.
The 2019 model adds several video related enhancements such as support for Dolby Vision and AI Upscaling.
As @Volts mentions, avoid the “tube” model. It is less capable than the Pro. It has known problems with high bitrate media such as 4K HDR rips. It does seem OK with 1080p Blu-ray rips, which have a lower bitrate, ~50 Mbps or less, than 4K HDR media, which frequently bursts above 100 Mbps.
Regarding Rokus, I thought they passed the lossy DTS 5.1 core when playing a DTS-HD MA or DTS:X soundtrack. However, I do not own one, so cannot confirm and could obviously be wrong.
My receiver does support even up to DTS:X. Why the Roku supports it? Not sure.
Some folks explained that their Roku 4640 (or whatever) supported DTS which is why there’s an option to allow it in Plex.
I’m not sure why, because Roku only seems to support what streaming services use, but DTS has got to be supported. There’s even an option to select "Dolby" or "DTS" as an audio output mode when not using "Passthrough".
