You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Payton Garner Author

Level 2

371 points

Apple Broke Dolby Digital 5.1 Output on Apple TV 4K

Not sure why nobody else is mentioning this, but figured I'd post to help others. One of these last few tvOS updates has completely broken Dolby Digital output (on Apple TV 4K, it seems).

I have a 2nd gen 4K model that had been fine until a recent update. I change the audio output in Settings to force Dolby Digital 5.1 for my speakers (Logitech Z906), but this suddenly no longer works! My speakers do not light the proper "Decode" light to indicate a true 5.1 signal, and the voices clearly come from left and right channels instead of just the center.

This was easy to confirm. I purchased a brand new 3rd gen Apple TV 4K (128GB) and it shipped with tvOS 17.1. I configured the audio output to force DD 5.1 and tested a movie... and everything worked perfectly. The "Decode" light indicated a 5.1 signal and voices, etc, clearly only came through the center channel. Then I upgraded to tvOS 17.4 and immediately tested the same movie, and it's broken! Nothing else changed.

Strangely enough, I have an old 1080p Apple TV running tvOS 17.4 (latest) and it still outputs Dolby Digital just fine.

I have provided this information to AppleCare as well as Apple.com/feedback. Kind of a ridiculous bug to go unpatched still. Hopefully someone will notice while we all sit here with broken audio.

Posted on May 7, 2024 10:30 AM

Top-ranking reply

Mcshoes

Level 1

38 points

Posted on Sep 16, 2024 10:59 PM

updated to TvOS 18 and 5.1 is broken. Apple TV connected to TV Samsung KS8000. HDMI ARC to Yamaha receiver. Only detects stereo. Please fix asap.

View in context

295 replies

Oct 7, 2024 2:08 PM in response to BUSHleagueBRO

What software that can't be named? My Apple TV says it's up to date (18.0) and I'm still getting PCM Stereo. Driving me insane.

Oct 8, 2024 11:54 PM in response to BUSHleagueBRO

The B fixed this for me. Thank you for the post. Extremely helpful!!

EddieKC

Level 1

22 points

Oct 13, 2024 8:38 PM in response to Payton Garner

Finally, it’s fixed in tvos 18.1! Just confirmed.

Oct 14, 2024 10:54 AM in response to nhojmselkcip

How do you do that?

Aug 16, 2024 6:17 AM in response to Payton Garner

The Apple TV is connected to my tv and the Sonos system is connected to hdmi arc. Regardless I think it’s something in the coding of the Apple TV software because everything has worked fine for over a year until the update.

Clwinbe

Level 1

29 points

Sep 14, 2024 7:10 AM in response to BUSHleagueBRO

Well thats it then for me.Two AppleTV4k go in the garbage. I’ll go elsewhere. My bet is they changed something in their the architecture and it’s up to all of the app vendors to alter their code. I wonder if we could get more traction by opening defects with each vendor? Too much work when there are cheap alternatives.

Payton Garner Author

Level 2

371 points

Sep 17, 2024 8:31 AM in response to ricardoalejandrodawson

I’m still on tvOS 17.6.1 (which I don’t guess matters), but this YouTube video you linked does not light the proper Dolby Decode light on my receiver and doesn’t play 5.1 for me. This is when played directly from Apple TV YouTube app.

My LG CX television is technically and AirPlay device, and when I AirPlay that YouTube video to the actual TV (nothing to do with Apple TV), I get the proper Decode light, but it’s only true 3.1, with no surround sound.

Payton Garner Author

Level 2

371 points

Sep 18, 2024 6:49 AM in response to _Czo_

Same experience with me with older 1080p Apple TV… still outputting Dolby 5.1 fine on all software versions.

This is also why I think it’s a codec change to how the 4Ks handle signals since they “also” support Dolby Atmos.

I just don’t get why tvOS 17.1 works and any later version does not. If you buy an Apple TV 4K from a store that it’s been sitting on a shelf forever, you may get 17.1 and can see it used to work. Upgrade and it instantly breaks. Something was deliberately changed.

Sep 19, 2024 5:16 AM in response to Urquhart1244

Before the update, my Apple TV defaulted to DD5.1 audio when set to auto. Sound came from all channels. After the update non Atmos sources play as PCM stereo. Nothing from rears or surrounds. The only thing that has changed was the update. Therefore, I think it's reasonable to suggest that the update is the culprit.

goto206

Level 1

32 points

Sep 19, 2024 5:18 AM in response to Urquhart1244

Just to be sure - my soundbar informs me that the sound being played is not in Dolby (red light instead of green). But does that mean that the sound is not necessary stereo? So a movie recorded in Dolby will be played as multichannel and I will hear the sound in the speaker in which I should hear it? It doesn't sound bad, but I'm worried that I just had Dolby sound (green light) before the update. This is all very weird to me.

Payton Garner Author

Level 2

371 points

Sep 20, 2024 11:13 AM in response to goto206

OP here…

Correct, I own an Apple TV A2169, 2nd gen.

My original post does also mention that I purchased a 3rd gen and witnessed it “break” instantly after updating from tvOS 17.1, with which it shipped, to a later version. I have since returned the 3rd gen, so I don’t know how they fare now.

Vader144

Level 1

32 points

Sep 22, 2024 1:01 PM in response to Payton Garner

Having a similar issue since I’ve downloaded TV iOS 18, my Yamaha digital set was giving me 5.1 digital sound with optical out and now it’s only giving me ProLogic. However, when I use the Apple TV app, Disney app, etc., on my LG TV, I’m getting 5.1 digital sound so clearly it’s the Apple TV unit and the download. I hope Apple comes up with a patch.

Payton Garner Author

Level 2

371 points

Sep 22, 2024 5:53 PM in response to llee

OP here. They’re probably not going to let you post this YouTube link and it’ll be removed.

Just search “Best 5.1 Surround Sound Test - By DTS” to find this video. It’s by 4K Clips and Trailers.

For what it’s worth, my Logitech Z906 speaker setup does not support DTS, so this won’t be relevant to everybody. My problem is just getting Dolby 5.1 passed through like it used to.

Sep 22, 2024 7:11 PM in response to Payton Garner

Same :/

Have had my Apple TV 4k work flawlessly for years until tvOS 18. Only PCM coming out of it now. Can verify that everything else connected to my Sony AVR sees all other codecs fine.

C’mon Apple…

dancerdj

Level 1

18 points

Sep 22, 2024 8:37 PM in response to dancerdj

The email from apple instructs me to use Atmos on my receiver or sound bar. As my perfectly functional, until the update, receiver predates this by several years that is not an option for me. Hope Apple solves this. Perhaps creating an option do go back to whatever setting was before this current update. Or make that setting for 5.1 actually output a 5.1 signal.

Apple Broke Dolby Digital 5.1 Output on Apple TV 4K