Netflix Dolby Atmos problems with new Apple TV 4k

Yes, this happens to me all the time, especially on Netflix. The audio will just cut out completely at some point during almost every Netflix show or movie that has Dolby Atmos. Other apps like Disney+ are also affected, but less consistently than Netflix. Typically if I exit the app, swipe around on the Apple TV homescreen until the UI sounds come back, and then re-enter the app, the sound will be restored. But not really an acceptable workaround for the most expensive streaming TV box.

I also have older versions of the Apple TV 4K and Apple TV HD in the house, on TVs with non-Atmos sound systems, and this NEVER happens on those systems. Only on the current-gen Apple TV, with current software.

Using it with an LG C1 TV and Sonos Arc soundbar, for context.

dearreid wrote:

Yes, this happens to me all the time, especially on Netflix. The audio will just cut out completely at some point during almost every Netflix show or movie that has Dolby Atmos. Other apps like Disney+ are also affected, but less consistently than Netflix. Typically if I exit the app, swipe around on the Apple TV homescreen until the UI sounds come back, and then re-enter the app, the sound will be restored. But not really an acceptable workaround for the most expensive streaming TV box.

This is identical to my experience, using a Samsung Frame 2021 and HW-Q800T soundbar. Very frustrating, especially to the rest of my family; this is undeniably the worst Apple product I've ever used. We've just switched back to using the Samsung's built-in apps most of the time, leaving the Apple TV turned off. The Samsung UX is clearly inferior - but it works reliably.

Tech blog and rumor site MacRumors has just picked up on this thread. Number of suggested fixes are proposed.

https://forums.macrumors.com/threads/some-apple-tv-users-complain-of-dolby-atmos-audio-issues.2343989/

I'm experiencing this issue, as well, with both an A110 and a 4700H. Very frustrating, Apple. I'm at the end of troubleshooting and have determined it is indeed isolated to the Apple TV 4K/Apple ecosystem.

I want my perfect Apple/Atmos experience back!

Please investigate and resolve this issue soon.

I have a problem with mine, got a new model Apple TV 4K 64GB for Christmas, it is plugged directly into my 2019 Sony AG9 4K OLED TV and is set to Dolby Atmos, the TV can accept and process this signal fine, but on my Apple TV I keep on getting incidents of no sound, I can be watching something in Amazon Prime or Netflix or even in the Apple TV app, and if I fast forward through the film or programme and start playing from a random position I can have no sound, but the sound was working fine when I started playing what I was watching.

Other times I can start watching something and click to skip the recap of previous episodes and / or the start credits, and when it goes to play the rest of the programme again I can have no sound but it was fine before clicking the skip option, again this is across different apps. I have to exit all the way back to the Home Screen and sometimes have to restart the Apple TV to get the sound to work again, and then it can play perfectly fine through the entire programme. It’s been like it pretty much since I got it.

Would be nice if Apple could fix this bug as it’s very annoying, I also use an expensive high grade HDMI 2,1 8K certified HDMI cable not a cheap one.

I’m also having this issue. A2169 15.4.1 connected to a Denon X4200W via a 48 Gbps HDMI cable. Connected to Ethernet with a gigabit internet connection. Primarily happens in Netflix, only when Dolby Atmos is enabled.

I wanted to add that I am also having this issue. What is interesting is that I think it is partially based on the sound system setup and how your receiver or pre-amp handles audio signals. I had an Arcam AV40 and it has a large front screen that displays the incoming sound format. While using the AppleTV I would see it 'flicker' from Dolby Atmos to multi-channel in all the time but I think the processor was able to just take it in stride and not interrupt the audio stream just drop the extra Atmos stuff. I would very occasionally notice a weird sound artifact like what sounded like the wrong sound coming out of the wrong speaker and that could all be related to this. This would also potentially explain why some people report no issues. It could be their receiver can just drop the extra Atmos stuff and keep playing the multi-channel sound.

Due to other issues with my AV40 (don't ask), I had to switch to a Marantz AV8805A processor. With that when the Atmos drops it causes the entire audio signal to drop and thus I get the stuttering and drops people report. In this case I think when the audio changes in any way the Marantz just works differently in that it tries to relock on the audio or something just the way it handles any changes in audio stream.

So to conclude I think it's clear the AppleTV has issues with Atmos and it's just manifesting itself differently depending on how your receiver or pre-amp handles audio streams but it is clearly not able to maintain a constant Dolby Atmos output.

For reference I have had the Atmos dropping issues on all sources of Atmos including Netflix, Apple TV, Disney Plus, etc. although it does appear to be the worst on Netflix.

I agree and have been saying different receivers/decoders handle errors in the MAT 2.0 Atmos metadata, which is created in the ATV4K and where I believe the problem is introduced, differently. Some may simply blank the audio to protect the speakers from potentially damaging pops/static, while others may replace that gap with the last good adjacent audio, like what CD players did to address errors due to dirt and scratches. Others may just blank the errant Atmos track, leaving the LPCM 5.1. There is also going to be variation in how far outside the MAT 2.0 Atmos specification the Atmos decoder/processor will accept before it detects an error. It seems that most mainstream receivers and soundbars will not cover up the Atmos dropouts, though.

I have found that the Atmos errors are more frequent in high video bandwidth streams. I sent an email to Ara Derderian, cohost of “HT Guys”, one of the few podcasts I listen to. I remembered that last year Ara said he was going to upgrade his ATV4K’s to the just released Gen 2. So, I thought I would ask Ara if he had experienced the Atmos problem. Ara replied to my email and said that he had never noticed any issues with ATMOS. He then tried Drive to Survive, which I had said was the most problematic for me, always cutting out within the first 10 minutes. Well, within 10 minutes, Ara said he heard the Atmos problems I was talking about.

Ara noticed that Drive to Survive was 50Hz. I had to go into my Denon app to confirm, as there is no display of the video frame rate on my Denon AVR or Sony TV. I had been speculating that higher bandwidth video and perhaps a busier Atmos track were factors in the Atmos dropouts, and the reason I have found Drive to Survive to be a most problematic program with its fast action and cuts. Now we have proof.

As further proof, I performed an experiment setting my ATV4K to 1080p, with both match Frame Rate and Dynamic Range ON. I played an entire episode of Drive to Survive at 1080p 50Hz, and the Atmos was flawless. This proves that higher bandwidth video, independent of Frame Rate, is the catalyst for the Atmos problem. This isn’t much of a surprise, except when you consider that the faster ATV4K Gen 2 is supposed to support 4K video at up to 120Hz due to having HDMI 2.1, an upgrade over the Gen 1 with HDMI 2.0. We also know that DV is not a factor, as Drive to Survive S01E01 that I used for this test, is not available to stream in DV. It is video bandwidth alone -- not Frame Rate or DV. It is also not just the 4K resolution, since 24Hz 4K is far less problematic than Drive to Survive. The same episode plays flawlessly on my Gen 1 ATV4K.

I question how credible those reports are based on the small number of reports I have seen, but it was enough for me to keep my Gen 1 on 15.3. I have no idea what the cause of the Atmos problem is. All I was able to do is figure out some conditions that aggravate the problem, such as high B/W video and Ethernet versus Wi-Fi. I also ruled-out several factors, such as DV, and I think it is safe to say that all the reports of dropouts when streaming only Atmos music are due to the normal blanking of audio by the AVR/Atmos decoder when the audio stream changes formats.

I believe the issue is introduced during the creation of the MAT 2.0 Atmos metadata stream that accompanies the LPCM 5.1 out of the ATV4K. I have posted a lot more on the MartinLogan forum here if you care to read more. Feel free to test out my findings and report back if you agree.

Thanks for that data point. Some reports were specific to the start of the songs, while most were non-specific me-too reports. I suspect this is a different issue, as in my experience, lower bandwidth videos can go many hours without the Atmos dropouts, so it doesn't seem possible that the same problem should affect Apple Music at all. I tested Drive to Survive forced to 1080p 50Hz and there were absolutely no dropouts. That indicates to me that the Atmos dropouts only occur with high bandwidth sources.

I suggest to everyone with the Atmos dropouts to switch to a Wi-Fi connection. Drive to Survive is a great test source as it is 4K 50Hz (season 2 and up are also DV), and in my limited testing Wi-Fi had only 1 dropout 26 minutes into the episode, while on Ethernet I had too many dropouts to count starting within the first minute.

img60 wrote:

I question how credible those reports are based on the small number of reports I have seen, but it was enough for me to keep my Gen 1 on 15.3. I have no idea what the cause of the Atmos problem is. All I was able to do is figure out some conditions that aggravate the problem, such as high B/W video and Ethernet versus Wi-Fi. I also ruled-out several factors, such as DV, and I think it is safe to say that all the reports of dropouts when streaming only Atmos music are due to the normal blanking of audio by the AVR/Atmos decoder when the audio stream changes formats.

I believe the issue is introduced during the creation of the MAT 2.0 Atmos metadata stream that accompanies the LPCM 5.1 out of the ATV4K. I have posted a lot more on the MartinLogan forum here if you care to read more.

Feel free to test out my findings and report back if you agree.

Also report back if you disagree. :)

I disagree... ;)

the appearance of the issue is too randomly, one day I can watch an episode without any dropout, the other day the problem starts a few minutes later and happens every few minutes. I don't see a way to find any rule it follows.

ATV4K->Yamaha A1080 5.1.2->Sony TV. ATV is hardwired, no ARC/EARC, TV is only monitor

Are you watching Drive to Survive? Drive to Survive at 4K 50Hz is the only meaningful test I have found as it produces consistent Atmos dropouts due to its high bandwidth. If you watch other shows that are 4K 24Hz (pretty much all other shows), the dropouts are too infrequent and random to come to any definitive conclusions. I have gone many hours with some shows -- even entire seasons -- without a dropout.

You need to test with Drive to Survive. Sorry if I didn't make that clear.

I always test with S01E01, though I don't know if it makes any difference. With a wired Ethernet connection, I always get dropouts within the first 10 minutes, usually within the first minute or two. I got no dropouts when I forced it to 1080p 50Hz, and I believe the relevant difference is the bandwidth rather than the resolution.

from my experience it doesn't any matter which season or episode you play. Yesterday I tested with latest beta (RC) S4 E4 and it happened within the first 5min. Didn't check yet with forced 1080p, maybe I can do later today.

iirc the reports of the issue started, when netflix started to provide AV1 codec for non mobile devices, posibly it's related to that.

While dropout the AVR shows "decoder off" for about 5 seconds, same behaviour when I switch manually audio format, e.g. german 5.1 to english Atmos. Seems to me that either there's a format change happen in the stream or the audio encoding task crashes and has to recover.

Have to add, that for a lot of weeks this issue happened only with Netflix, not ATV+ for example, and that provides a clearly higher data rate than NF