Atmos 7.1 demos not working on Apple TV 4k

Video Playback
1

Hi,

I’m trying to play Dolby Atmos trailers on my ATV 4K and a 5.1.2 system and I’m trying to understand why some don’t work and where the problem is.

Trailers are from Dolby Trailers - The Digital Theater
I’m using those with DD+ (not TrueHD which I’m aware doesn’t work on ATV) and selecting the correct audio track.

Only one DD+ trailer is 5.1+Atmos and works as expected, all others are 7.1+Atmos and when I play those, I get regular 5.1 output without Atmos.

Is this a limitation of Infuse? Or is it the receiver who doesn’t know what to do with the Atmos data in this case?

2

What receiver do you have? Can you use mediainfo to confirm atmos in the files?

3

If the trailers have multiple audio tracks (TrueHD atmos and dd+ atmos) you might run into issues.

4

The chain is ATV 4K → HDFury Arcana → Sonos Arc (incl. rears and sub)

I did check with with MediaInfo and the files do all include Atmos. The only difference is the number of channels 8 (7.1) vs 6 (5.1).

5

Can you post the mediainfo dump for the affected file?

6

This shouldn’t be an issue if the software is well done. As I said, I made sure to select the correct track in Infuse when playing (and just in case tried all the other ones, too).

That said, I still wanted to give it a try and actually removed all other audio tracks from the file (making sure that there is no re-encoding done and double-checking with MediaInfo that that output indeed contains only the DD+ track including Atmos). Doesn’t change anything, though.

7

This is for the file that works:
Audio
ID : 2
Format : E-AC-3 JOC
Format/Info : Enhanced AC-3 with Joint Object Coding
Commercial name : Dolby Digital Plus with Dolby Atmos
Codec ID : A_EAC3
Duration : 1 min 50 s
Bit rate mode : Constant
Bit rate : 448 kb/s
Channel(s) : 6 channels
Channel layout : L R C LFE Ls Rs
Sampling rate : 48.0 kHz
Frame rate : 31.250 FPS (1536 SPF)
Compression mode : Lossy
Delay relative to video : -67 ms
Stream size : 5.93 MiB (5%)
Language : English
Service kind : Complete Main
Default : Yes
Forced : No
Complexity index : 12
Number of dynamic objects : 11
Bed channel count : 1 channel
Bed channel configuration : LFE

This is the file that doesn’t work:
Audio #2
ID : 3
Format : E-AC-3 JOC
Format/Info : Enhanced AC-3 with Joint Object Coding
Commercial name : Dolby Digital Plus with Dolby Atmos
Format profile : Blu-ray Disc
Codec ID : A_EAC3
Duration : 3 min 5 s
Bit rate mode : Constant
Bit rate : 1 664 kb/s
Channel(s) : 8 channels
Channel layout : L R C LFE Ls Rs Lb Rb
Sampling rate : 48.0 kHz
Frame rate : 31.250 FPS (1536 SPF)
Compression mode : Lossy
Delay relative to video : 7 ms
Stream size : 36.7 MiB (2%)
Service kind : Complete Main
Default : No
Forced : No
Complexity index : 16
Number of dynamic objects : 15
Bed channel count : 1 channel
Bed channel configuration : LFE

8

The DolbyAtmos is not working with the last tvOS 14 on all the apps …

9

Are you running 14.2 beta? The beta breaks atmos. Have to wait for Apple to fix as you can’t downgrade tvOS.

10

I have the same issue with those demos Using Infuse 6.5 on TvOs 14.01
I choose the DD+ 7.1 (Atmos) Sound track but get no Atmos from Infuse.
Atmos is still working on ITunes and Disney+

11

@JarvisMeier @christophemanuel31.1

This has unfortunately nothing to do with the problem I described here.

a. In my case, Atmos works on the 5.1 atmos file but doesn’t work on the 7.1 atmos file
b. I tested before upgrading to tvOS 14
c. Apple just released 14.0.1 which seems to fix the problem where atmos wouldn’t work at all in some apps, yet the problem I mentioned in my initial message remains.

12

I’d be curious to know what kind of receiver and setup you’re using. Do you have a proper 7.1.x setup or 5.1.x as I do?

13

I have a 5.1.2 setup (Surround reciever and 8 speakers)

14

Would you be able to upload a sample of one of these problematic videos?

15

My bad, I should have directly mentioned the files in the initial post, as they are both directly available on https://thedigitaltheater.com/dolby-trailers/

File that works:
Nature’s Fury (Dolby Digital Plus ATMOS)

File that doesn’t work:
Leviathan

(or pretty much any other file on that page, that says “Dolby Digital Plus ATMOS” except the one above)

16

It looks like Leviathan.m2ts has 2 audio tracks.

  • Track 1 - Dolby TrueHD + Atmos
  • Track 2 - Dolby E-AC3 + Atmos

Most likely, Infuse is selecting the TrueHD track by default. Can you try playing this video again, and selecting Track 2 manually? This can be done via the Audio tab of the Playback Settings menu (swipe down while a video is playing).

DOLBY_NATURES_FURY_1920x1080_DD+_ATMOS-thedigitaltheater.mkv has only a single audio track, so no issues there.

17

Selecting the correct track is something I’ve actually done as I mentioned in my initial message. I’ve also tried removing all but the “Dolby E-AC3 + Atmos” track… same result: no atmos!

Dolby E-AC3 + Atmos track in my case only works if it is 6 channels, then I get Atmos. If it’s 8 channels, I only get regular 5.1 (no atmos).

Obviously, as I stated earlier, in only have a 5.1.2 system, so I’m trying to figure out, if it is Infuse that forces the downgrade to regular 5.1 or if it is a AppleTV limitation, or if it is my “receiver” (Sonos Arc) who does that.

18

And I know you said it at the beginning but confirm you are playing this through Apple TV 4K, not 4th gen/HD which doesn’t support atmos?

19

I tried these on my nvidia shield which does proper pass through and the Dolby digits plus tracks with atmos do not work. They only play as regular 7.1. The TrueHD tracks do play with atmos.

I’m going to say that their is something up with the files. That does seem right considering dd+ seems to be limited to a max of 8 channels so regular 7.1 or 5.1.2.

20

Yes, I’m playing it on AppleTV 4k, and just to repeat: The 6-channel ATMOS file I mentioned works perfectly, I can both hear but also confirm in the receiver, that it is getting Atmos.