Apple Broke Dolby Digital 5.1 Output on Apple TV 4K

I have more Apple TV's, a 2015's 4th generation HD model (A1625/32GB) and a 2022's 4k version (A2843/128GB). Both updated to the same tvOS version (18.0/22J357). Both of them configured in the Audio Format setting to Change Format and Dolby Digital 5.1. (I have a third one (a 2017's 4k), but it currently are lended over to one friend, so i can not test it)

Only stereo sound came out from the 2022's version in any of the applications have I tried (Netflix, VLC, Youtube). In the other hand, the 2015's model worked fine, the receiver displays Dolby Digital and all of the speakers was sounded perfectly.

My audio setup is a little bit weird and old :D, I have a Creative Labs DTS/DD5.1 optical decoder from the early 2000's which is connected to a mid 2000's 5.1 analogue wooden speaker system. The Apple TV connects to it via an HDMI-Optical Audio extractor device, which was worked fine in the last decade. I tested both Apple TV's with the exactly same configuration, I mean disconnected all of the cables from the old one, and replaced the Apple TV with the other one.

Not necessarily what you want to hear, but I have found that using an Amazon fire stick 4K and using the Apple app (not Apple+) then you can stream your iTunes movie library (and other sources) from there.

Because I have lip sync issues with Atmos content from the Apple TV box, I might just end up selling it on altogether.

Apple TV to AVR 5.1 Dolby decoding no longer available, just 2.1 PCM since the 18 iOS software update. I’m a United Kingdom customer, for what it’s worth. Apple Tech support, please do your thing…I’ve got movies to watch.

I have Apple TV HD and after the update to TVOS 18 a few days ago, I no longer get Dolby 5.1 except in the YouTube app.

It has been connected to an older Bose Lifestyle system and older Sharp TV and has never had this issue. I tried restarting, unplugging cables, forcing Dolby 5.1 but nothing worked. Is this only affecting folks with older TVs and surround systems?

I have one of each: Apple TV 4K and Apple TV HD. What I want to try to make clear is that both models have the problem under tvOS 18.0. Neither had the problem under the most recent previous release. The problem I'm referring to is that when the Audio Format is set to

Change Format: On

New Format: Dolby Digital 5.1

no multichannel output goes out of the devices through HDMI or S/PDIF.

(I think I neglected to use the phrase "New Format" in my previous posts. Sorry.)

Remember, when you set Change Format to Off, the 2nd option (the option to assign "New Format") is no longer available. Then the Audio Format setting defaults to Auto. The Auto setting allows both models of Apple TV to send 5.1, but only if the AVR, or Sound Bar, or whatever sound system connected synchronizes with the Apple TV in such a way that the Apple TV recognizes that sound system and sends multichannel audio. AFAIK, there's no published list to reveal what sound systems allow Apple TV to sync and sent multichannel audio when the Auto setting is active.

If you want to observe the problem, just make these settings in Audio Format from the Audio section of Video and Audio in Settings:

Change Format: On

New Format: Dolby Digital 5.1

Then play a multichannel audio title from a streaming app other than Home Sharing or YouTube. The output will only be stereo (2-channel).

I hope that is a useful explanation.

Exactly the same problem here (in the U.K.) after auto update to TV OS18 with my 1st gen 4K TV Box. I thought it was a problem with the Netflix app so updated that. Now I've tested my other streaming apps and I can't get 5.1 sound from anything. I have over 100 films purchased in iTunes and no 5.1 sound from them either.

I have a Denon avrx2200 receiver and it clearly tells me what sound I've got on the display and I'm now back to Dolby surround.

I wish I never turned auto update on but I've never had an issue before. Personally I'm fuming about this because I always listen to 99% of content in 5.1 sound. This is a huge step downwards & I feel like I'm missing half the content.

I encourage everyone to call in to report this issue either via the support app on their iPhone or actually calling Apple support to provide diagnostic data. The more voices we add to this the more likely we will get it fixed.

Yes, I now absolutely regret having auto update on and allowing both of my units to get broken. I will never have that feature selected in the future, if I continue to use Apple TVs, that is. If Apple isn't going to fix this, I wish they'd allow an option for going back to 17.

I have updated to the version that must not be mentioned here. I can confirm that the issue is resolved for me with a 1st Gen 4k box going into an LG C1 then HDMI (earc) to LG SN9YG Atmos soundbar. Atmos works (as it always did) and Change Format gets me DD5.1 again instead of PCM Stereo. I’m sure the fix will carry on to the public release of 18.1🤞🏻so hopefully not too much longer to wait.

If any of you are on the 18.1 beta, you can provide feedback here with the Feedback Assistant: Bug Reporting - Apple Developer

The beta developers might take this type of report a little different (more serious?) lol

I am facing the same issue with same setup, anyone can help to sort out this issue or when will apple will address this issue too bad experience

I can confirm. I turned on my AppleTV 4K today, and noticed I had to accept the "Terms and Conditions" which usually means I received an update. I checked my AppleTV 4K version and it is TvOS 18. Any content other than Dolby Atmos movies will not decode correctly. It will show up as PCM (2.0). For example, I am watching "The Man In The Iron Mask" on my AppleTV 4K which is natively English Dolby 5.1, AAC (according to Apple's website) but decodes as PCM 2.0. I know some of you will argue that "it means loss-less" which I will tell you now, it is nonsense, because there is a sound quality difference between my AppleTV 4K vs using the Apple TV Application on my LG TV. On My LG TV using the AppleTV application, it decodes correctly as Dolby Digital+ and has a much fuller sound. I am willing to guess, the update broke the AppleTV 4K device and aside from movies with Dolby Atmos, it is playing in Stereo 2.0 and when my AVR upconverts it, it sounds terrible. Please FIX the problem if you want me to continue to use your device. I could easily just use the native AppleTV application on my LG, but because I want to like Apple products, I am going to ask that you fix the problem! PLEASE SEE IMAGE BELOW of APPLETV4K vs THE LG APPLETV Application.

The Apple TV box has always done PCM Multichannel out, for the “Auto”/best quality audio format setting. PCM does not mean 2.0 per se; it can be up to 7.1 for Apple TV, if the HDMI connection allows for that. The Apple TV box will not output Dolby Digital Plus, nor did it do so recently, even when that was the input. There is no passthrough option (since tvOS 10, I think).

1. While the conversion to PCM Multichannel will be lossless, your audio equipment can decide to treat these two formats differently, in post-processing. That may depend on your audio system and/​or its settings.
2. There could be HDMI bandwidth restrictions that force a lesser format, but if you are getting Dolby Atmos, then this wouldn’t apply.

I am willing to guess, the update broke the AppleTV 4K device

It didn’t. It just says 7.1 on my 7.1 AV receiver for Apple TV 4K on tvOS 18, for 7.1 sources.

Please FIX the problem… I am going to ask that you fix the problem!

Apple will not see your concern here in the forums. To notify Apple on structural issues, please use the feedback form. Feedback - Apple TV - Apple

It works on my Apple Tv 4K. You have to play a film and then, while playing, you have to change the audio output as Edwy7580 mentioned. It doesn‘ t work in pause mode.

Until 18.1 is released, it isn't really fixed.