Level 2

401 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

off911

Level 1

26 points

Posted on Oct 25, 2024 12:50 AM

The problem was solved with the latest update released for the Apple TV 4K.

I signed up on Apple's website to also receive beta updates and then the option to download a beta version on the streamer itself was opened. I downloaded an update and the problem was solved. At first, I manually enabled the Dolby Digital 5.1 option in the settings, then I set it back to auto, after I saw that it was indeed playing Dolby Digital. When I put it back to auto, it now knows how to play Dolby Digital with the appropriate content and Dolby Atmos with the appropriate content. very happy!

[Edited by Moderator]

View in context

Similar questions

305 replies

Payton Garner Author

Level 2

401 points

Sep 23, 2024 9:44 AM in response to Community User

Gotcha.

Yeah, I think the best hope is to keep posting bug reports to the official Apple Feedback form and, if you have AppleCare especially, call them to have it escalated. The more often a senior support advisor sees the issue, the more likely they’ll start digging into whatever they did to break it.

I know you’re doing your part and then some.

Sep 23, 2024 5:29 PM in response to Darksol360

I've just turned on my Apple 4K TV box 1st gen to watch something off Netflix.

I thought it was a Netflix problem but first but it's happening and every app that I have and any films that I purchased too in iTunes. Everything worked fine until this TV OS 18 update. Never turned on auto update.

I have a Denon AVRX2200 Receiver that displays what audio I am getting. I can change sound mode but I do not get the option of Dolby Digital anymore. Just plain old surround sound.

The Apple 4K TV first gen is part of my home cinema setup and I consider 5.1 sound crucial to watching anything.

If someone knows how to roll back to the latest version of OS 17 I would like to know how please.

_Czo_

Level 1

50 points

Sep 24, 2024 12:13 AM in response to MesserGalileo

None of my Apple TV's (A1625, A1842, A2843) will produce an 5.1 sound when watching trailers from the Apple TV+ application (Kingsman: The Secret Service; The Family Plan). The "Change Format" setting still configured to "Dolby Digital 5.1".

Sep 27, 2024 3:31 AM in response to Payton Garner

I have a Sonos Arc with a eArc TV and the latest Gen Apple TV 4K. I had always received and played Atmos from several TV streaming services and I recently lost Atmos on Netflix, Prime, and Disney. On some it was gone and on some it showed as "Spacial Audio." However, some services (Max, Paramount Plus) were still working OK with Atmos (TVOS 18.1).

After checking all settings I ended up going nuclear and returning the Apple TV to factory settings. That didn't work either. But I later found that if I waited a day, the "Spacial Audio" changed correctly to "Dolby Atmos." I have no idea what fixed it other than time. And it seems to work fine now.

This only happened on Video apps and music apps such as Tidal, continued to correctly sense the Dolby Atmos.

PS: I didn't check for changes the TV firmware but when it updates, it gives me a whirly bird on start-up so it probably is the same.

Sep 27, 2024 5:16 AM in response to Community User

I have Prime Video, Disney+, Paramount+, Netflix, Sky Go and YouTube installed on the box. All were affected by the issue on the 1st Gen box. They all work correctly outputting 5.1 on the 3rd Gen.

Although the issue seems to be gone for me for now I utterly, utterly regret not spending the bit extra an eARC TV when I bought my last one.

Sep 29, 2024 2:33 AM in response to Payton Garner

As others have stated, I can get 5.1 from YouTube and that's the only app. All others had 5.1 broken at the 18 update. I have a 1st gen 4K. The workaround doesn't work for me. I've been trying to mess around and find a different workaround but nothing has helped. I see on my receiver that the Apple TV is switching the audio signal when I start a program that should have 5.1, but then just goes back to stereo. This switch is normally where it would switch and stay on 5.1.

[Edited by Moderator]

Windh

Level 1

104 points

Sep 28, 2024 2:58 PM in response to Payton Garner

I have the same issue. I must use a splitter to get optical from HDMI since my cheap receiver has no HDMI input.

However, the fact that the 'Change Format' option still is there in tvOS 18 should indicate that Apple haven't removed this feature, but rather messed it up with the update, no?

Sep 30, 2024 12:41 AM in response to Payton Garner

Adding more fuel…

Went to watch a movie tonight and discovered I’m also only getting stereo in all apps :(

ATV on tvOS 18 > LG oled > Denon receiver via ARC. It’s an older receiver that doesn’t support 4K hence why I’m using ARC. All my other devices work fine in the same scenario. So hopefully Apple fixes this ASAP.

ATV had been working fine previously. What’s funny is I specifically wanted to watch a movie on ATV+ but nope guess not

Oct 3, 2024 10:15 PM in response to Payton Garner

Thank you.

Ah yes, I did see that post. Assuming I read the post correctly the method did not fix the issue for me.

Assuming they meant press and hold the TV button on the remote, swipe to Audio, select a different speaker and deselect TV speakers, then deselect the other speaker and re-select TV Speakers.

Payton Garner Author

Level 2

401 points

Oct 4, 2024 11:49 AM in response to Community User

Interesting. Sounds plausible to me. Here's that documentation on Apple's Dev website for the technical crowd:

AudioConverterFillComplexBuffer(_:_:_:_:_:_:) | Apple Developer Documentation

Also might explain why this works for some apps and not others. If that particular app is using another method or API to convert audio, it may not be affected.

Payton Garner Author

Level 2

401 points

Oct 16, 2024 10:09 AM in response to Lonesomepine

My original post for this discussion is about a 2nd gen 4K.

I guess it took tvOS 18 for this bug to appear for others, but I’ve had this issue since sometime in early 2024, well before tvOS 18. But tvOS 18 did break it for my older 1080p Apple TV, which had been working fine.

Oct 25, 2024 11:00 AM in response to off911

I can do this with the latest update but:

I have to do it for EVERY app. It only sticks for each app individually.
I have to do it EVERY time I turn on the Apple TV. Doing it once doesn't solve it forever.

Are you noticing either of those or did switching 5.1 on/off in Change Format solve it globally indefinitely for you?

Oct 28, 2024 8:46 AM in response to Payton Garner

So I just updated to the latest tvos 18.1 public released version. And as I already noticed on the b versions, the problem has not been fixed for me. Switching to dolby 5.1 does not give me surround sound. The light which indicates that it is receiving a dolby digital 5.1 signal on my logitech z906 doesn't light up. This is very disappointing, as I beginning to lose hope if it will ever be fixed.

Payton Garner Author

Level 2

401 points

Oct 28, 2024 9:45 AM in response to Payton Garner

Original Poster here...

I have updated to tvOS 18.1 (just released to all) and can confirm the issue is NOT fixed for me.

I tried various sources like Apple TV+, Netflix, YouTube, Max (HBO)... none of them light the proper "Decode" light to indicate Dolby 5.1 on my Logitech Z906 speakers. And it's obvious the audio still sounds terrible.

This is extremely disappointing. My gut says it was never going to work. Whatever issue I have predates anything on tvOS 18 that others only seem to experience when upgrading to that version. I feel like perhaps Apple transitioned how audio is handled around tvOS 17.3 or 17.4, and this is not a "bug" to them.

It's unfortunate, but I cannot invest anymore in this platform when surround sound that was working fine is taken away from me. Not even buying a new device solves the problem, but that won't even be a consideration going forward.

I hope this fixes whatever issue others are having, though.

Oct 30, 2024 12:10 PM in response to Payton Garner

Hello,

I still have the same problem with iOS 18.1 , in auto I have Dolby Atmos or stereo, but still no Dolby digital 5.1.

I have it only by forcing it, but in this case I lose the Atmos. Apple, please do something.

It's an Apple TV 4K 2017

This thread has been closed by the system or the community team. You may vote for any posts you find helpful, or search the Community for additional answers.

Apple Broke Dolby Digital 5.1 Output on Apple TV 4K