Only Dolby Audio output instead of Dolby Atmos on Apple TV 4K

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Level 1

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Only Dolby Audio output instead of Dolby Atmos on Apple TV 4K

Dolby Atmos was not working on Apple TV 4K with latest tvOS 14.4.

My TV (LG Nano Cell) supports Dolby Atmos input and decoding. With TV built-in apps like Apple TV+ and Netflix, Dolby Atmos could be played correctly, the Dolby Atmos logo will be shown on the upper corner of the screen.

But when playing the same content on Apple TV 4K which was connected directly to TV, Dolby Atmos can only be played by downgrading (converting) into normal Dolby Digital.

To be specific:

In tvOS settings, Audio Format had already been set to "Change Format - Off", "Dolby Atmos - On" (Audio Format - Auto, Atmos Available).

In LG TV settings, the HDMI audio input format had been set to "Bitstream" (another option is "PCM", which means stereo), and Dolby Atmos decoding function had also been enabled.

With all these setups above, no Dolby Atmos output from any app on Apple TV 4K, including Apple TV+ app.

With the same settings of LG TV, the same HDMI input port on TV, and the same HDMI cable, no matter it was a local video file on my hard drive , or Netflix application, and no matter the audio format was TrueHD or Dolby Digital Plus / E-AC-3, Dolby Atmos can be always recognized and played by TV from a Windows PC without any issue.

So it seemed to me that this was a problem of Apple TV 4K or tvOS, since Apple TV 4K was the only device which I had that cannot output Dolby Atmos to TV.

Posted on Apr 7, 2021 5:20 AM

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Answer 1

Best reply

Urquhart1244

Community+ 2024

Level 10

139,860 points

Apr 7, 2021 9:40 AM in response to nfsking2

Apple TV 4K outputs Dolby Atmos in uncompressed Dolby MAT format, which many modern AV receivers can decode, but possibly not your TV. Play audio in Dolby Atmos or surround sound on your Apple TV - Apple Support

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Answer 2

Jpdev001

Level 1

44 points

Apr 8, 2021 4:45 AM in response to nfsking2

As mentioned above - sounds like an incompatibility with your TV. You didn't mention speakers or whatnot, but is it possible to try plugging your Apple TV directly into your AVR or soundbar? This is the most reliable way to get surround out of the Apple TV.

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Answer 3

nfsking2 Author

Level 1

4 points

Apr 8, 2021 6:48 AM in response to Jpdev001

There was no any AVR or soundbar has been used, just Apple TV directly into TV set.

As mentioned above, the TV could decode Dolby Atmos, with Atmos logo as confirmation.

And because there were no issues with any other video playing devices with the same settings and connections, it was no chance that this issue was caused by compatibility of the TV.

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Answer 4

Jpdev001

Level 1

44 points

Apr 8, 2021 7:09 AM in response to nfsking2

The TV may work with it's own apps, but is likely incompatible with Apple TV. Apple TV works best when plugged directly into an AVR. I suggest sending feedback to Apple with the make and model of your TV.

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Answer 5

Apr 8, 2021 10:22 AM in response to nfsking2

You will need a Dolby Atmos speaker setup to enjoy the immersive sound of Dolby Atmos. With just your built-in (stereo) TV speakers, you will not get directional dome sound from behind or from above that Atmos intends to deliver. And if such capability is not detected, the the Apple TV will not output such a signal.

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Answer 6

Jpdev001

Level 1

44 points

Apr 8, 2021 11:19 AM in response to Urquhart1244

Urquhart1244 wrote:

You will need a Dolby Atmos speaker setup to enjoy the immersive sound of Dolby Atmos. With just your built-in (stereo) TV speakers, you will not get directional dome sound from behind or from above that Atmos intends to deliver. And if such capability is not detected, the the Apple TV will not output such a signal.

It's possible the TV has the ability to process Atmos (hence the on-screen Atmos logo reportedly appearing via the TV apps). Of course it won't be actual surround sound Atmos, but a DSP processed sound designed to "widen the image." Most likely culprit is the TV does not support the codec/data stream used by the Apple TV. Similarly, I'm finding Apple's AirPlay 2 is even worse: some media content plays on some TVs, others... nope.

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Answer 7

nfsking2 Author

Level 1

4 points

Apr 9, 2021 12:57 AM in response to Urquhart1244

It's not true.

There is no different between the built-in tv speaker and speaker like sound bar in theory. Whether the sound is immersive or not is totally another topic.

Yes, I know Apple use high bandwidth Dolby (MAT) output form, but it's only makes Apple TV cannot output Dolby Atmos when using ARC connection from TV to the external sound system, not direct connection, because LG TVs are officially confirmed the support of Dolby MAT codec, along with Dolby TrueHD and Dolby Digital Plus.

And again I want to point out, that in Apple TV audio settings, it is confimed that dolby Atoms is available.

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Answer 8

David879

Level 1

4 points

May 8, 2021 7:17 AM in response to nfsking2

I’m having the same issue, Dolby atmos is showing as available but not actually working only with the Apple TV device.

When I’m using the native applications on LG TV atmos is working.

I tried speaking with an apple representative and had no luck with them.

I’m using LG nano85una and Apple TV 4K.

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Answer 9

May 28, 2021 7:25 AM in response to David879

Did this ever get fixed? Ive just got Nanocell 86 for a great price and only the Apple TV doesn't show Dolby Atmos on the tv, all the native apps work fine with it and it shows immediately, can only think this must be a compatibility issue with Apple and LG and this is with the new 4K box (2021), HDMI 2.1 cables and all settings correct. It even shows Atmos capable in the Apple TV settings.

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