Netflix Dolby Atmos problems with new Apple TV 4k

I personally have never heard the Atmos problem on my Gen 1, but @Golfergb just reported that 15.4 brought the Atmos problem to his Gen 1. My replacement Gen 2 rarely had the problem on 14.7 when I received it in December, but I finally caved to Apple's obnoxious update nag screens, and 15.3 was at least an order of magnitude worse. You could connect both Gen 1 and Gen 2 to your receiver, as I did, for more convenient testing.

I believe the problem is likely fixable in software, since the version of tvOS made a significant difference in the frequency of the problem, but I am very doubtful Apple will make any real effort to do so, since the Apple TV isn't much of a money-maker for them. We shouldn't have to put up with this unacceptable Atmos performance in a premium streamer, and Apple should do something to make this right, but they won't even publicly acknowledge the problem (beyond what Customer Service reps have told some people).

chrispyer wrote:

@bgmeek

I have no problems with Roku or Fire TV on anything Atmos. I'm running a 5.4.2 on a Denon also. This

Atmos popping and cutouts started happening after the 14.7 TVOS updates.

Yep. I believe you and I'm sorry to hear about it. I didn't mean to come off as an Apple fanboy who isn't periodically frustrated with lingering bugs in Apple products and some arguably poor design decisions. I also really didn't mean to imply that Apple doesn't have a Dolby Atmos problem here that needs addressing (or should've been addressed by now).

I was just sayin' that Dolby Atmos issues aren't unique to Apple TV 4K devices and that AV component interoperability is complex, so it's reasonable to be patient and examine every component when issues occur in a home theater setup.

We don't really know if we're talking about just one issue in this thread, or if there are multiple issues with similar symptoms (some of which may lie in downstream components and/or be triggered by 3rd-party apps).

I saw this interesting blurb in Apple Support's article "Set up Dolby Atmos or surround sound on Apple TV with a sound bar or AV receiver":

Some sound bars and AV receivers support Dolby Atmos, but don’t support video formats like HDR10 and Dolby Vision. In this case, you can plug your Apple TV 4K into either the sound bar or AV receiver to play sound in Dolby Atmos. Or you can plug your Apple TV 4K into your television to watch video in HDR and Dolby Vision. To do both, you need a television or an AV receiver or sound bar that supports both Dolby Atmos and high-quality video formats. Apple TV 4K uses a high bandwidth form of Dolby Atmos that doesn’t work over ARC connections.

Again, my knowledge is layman's superficial, but this "high bandwidth" statement supports what I've read that ATV4K converts multichannel digital audio streams to uncompressed PCM before sending it along... If this describes the way Apple supports Dolby Atmos, perhaps they should implement a pass[the buck]through settings option for digital audio that relies on downstream components to decode/render the source audio content (despite their minimalist approach to settings options).

IOW, Apple's Atmos support may be perfectly legit and bug-free (as my Sony sound bar appears to believe), yet it could still cause problems on some home theater setups that work fine with other media devices' Atmos implementations.

I think Ikrupp jumped the shark though! On the same receiver, I have a Roku, Amazon Firestick and from the TV(LG C9) using EARC no problems whatsoever with Atmos on Netflix, HBO, AppleTV+ or Disney+. Only happens on the second generation AppleTV+ and does not happen on the first generation, I own both and tested both. It is highly unlikely IMHO for the problem not to be with the AppleTV 4K second generation. If Ikrupp has no such problems, that's a good thing. We that do are not imagining it.

Anyone who is talking to Apple Support get an ETA for when this bug will be fixed? I can't believe it's still around!

I just got a new gen AppleTV to replace the old AppleTV 4k because I wanted Youtube 60fps, but now all of a sudden I'm getting sound cutting out on Dolby Atmos content. I've only experienced this in Netflix app, and if I restart the app it temporarily resolves it for a few minutes. Restarting Apple TV completely will fix it for maybe 30-40 min. Really frustrating. My setup is not ARC. It's Apple TV -> Denon X3300W -> 5.1.2 sound system

I was able to return my 2021 ATV 4K to BestBuy and picked up an Nvidia Shield instead and am very glad I did.

Now I can enjoy Atmos shows without sitting there waiting for the Audio problems to start. I no longer have to watch for the latest TVOS updates, apply them, only to discover that nothing has changed.

I would advise anyone who can return the ATV to do so…why live with this aggravation?

I have noticed that when i unplug the apple TV and let it rest for a couple of second and plug it again it solve the problem for at least a couple of hour. The stuttering get back when i stop using the Apple TV and i go back again to use it.

You didn’t mention the MAT 2.0 stream that accompanies the LPCM 5.1 stream and carries the Atmos metadata. Months ago, I posted my thoughts that this is where the problem is. I believe the ATV4K Gen 2 is introducing timing issues or other errors in the MAT 2.0 stream. I believe the Atmos decoding is fine, since other audio formats have no issues. I have found certain programs, such as Drive to Survive on Netflix, to be more problematic. I believe this is because the video has more bandwidth and perhaps a busier Atmos track.

HDMI cable quality made no sense to me, since it seemed absurd that it could target Atmos only and leave all other audio formats and more susceptible video completely free of artifacts. I initially considered a thermal problem, but quickly ruled that out when I had dropouts within a minute or two of plugging in my ATV4K. My Gen 1 unit has been flawless in the same setup. And yes, a bitstream option would obviously solve the Atmos problem, and this has often been suggested here and in other threads.

I get a chuckle at posts that say the problem is 100% software. It isn’t that simple. For example, there could be a subtle hardware change that was overlooked in the software. For example, the software could have a bit of asynchronous code that expects the hardware to run at a certain speed. With the faster Gen 2 hardware, this could cause a timing issue. This could possibly explain why the Gen 1 and Gen 2 ATV4K do not behave identically with respect to the Atmos issue, assuming the same software. However, I do believe that the problem can be fixed or mitigated through software, since the Atmos problem was an order of magnitude less frequent on tvOS 14x.

Apple has been a major disappointment. If they aren’t going to fix the problem, either due to lack of effort or talent, they should give us a refund. We should not have to put up with these Atmos problems.

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.

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 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.

My setup is the same except I have a Denon 4300H and a cheap 3ft Cable Matters HDMI 2.0 cable, which is more than up to the task. DtS is the only meaningful test as it is 4K 50Hz and consistently produces dropouts for me. Nearly everything else is 24Hz, so significantly lower bandwidth, and can go many hours without a dropout.

After installing 15.5 and being hopeful, sadly, the problem has returned.

I watched two episodes of "The Essex Serpent" on AppleTV+ today after playing Atmos Apple Music for several hours without any problems. That didn't work very well at all before -- if the box was up for a long time, it would fail on the first song. Unfortunately, "The Essex Serpent" had two glitches, near the beginning of each of the two episodes I watched today. They were the same kinds of glitches from "Drive to Survive" -- silence, then a chopping sound that gets faster and faster until finally the audio resumes and synchronizes. Each time, I backed up and was able to hear the part I missed without any problem.

It's odd that it happened within the first minute or so of the show, and then didn't happen again until the start of the second episode. The fact that Apple Music seems to work (even when showing cover art and the scrolling lyrics) might indicate that there's a conflict between the audio and the decoded video, which was Dolby Vision.

Right now, I'm planning on restarting the AppleTV 4K every night and hopefully it won't have the problem the next day as the Atmos sound is spectacular when it works properly.

For the record, I am using gigabit wired Ethernet to the 2021 AppleTV 4K connected to the "Media Player" input of my 9 month old Denon 8500HA. The TV is a 4 month old Sony A90J. I don't want to put the AppleTV in 1080p mode because the point is 4k programming. I have never had a dropout if I use the AppleTV app built into the TV's GoogleTV operating system.

This thread is about an issue that only affects Dolby Atmos, and only on Gen 2, though there are some reports that the latest tvOS is now affecting Gen 1. Try a system restart of the ATV4K. Doesn't sound like an HDMI cable issue. Did you try switching inputs on your soundbar?. If that doesn't help, it does sound like your ATV4K has a problem, since your other devices don't have this problem. Either that, or another tvOS regression.

" Apple should offer everyone with a Gen 2 a refund, but it would likely take a class action suit for that to happen. "

Better they fix it, I don't see actually no alternativ for my use, it's fast, smooth, has a superior picture quality and -most important for me- the automatic frame rate switching from 23,97 up to 60 fps.

Switchimg to wireless solved the problem entirely for me (use it only for streaming, no BT, no airplay or homepods), had not a single dropout.

Of course it's just a workaround and not a solution, so let's go on poking Apple to fix the problem on the root

People just coming into this discussion should read a bunch of comments before they post

1. It is definitely not just Netflix. Apple TV, Paramount Plus, Etc. all have dropouts. If they don't for you, you are lucky
2. You already have great cables (I would hope if you have an Atmos setup). Don't waste your time and money changing them.
3. Why in the world would you switch to 1080p??????? I would get rid of the Apple TV before I even tried that to see if it worked
4. I forget which update but it is now an issue with 1st gen 4k's as well
5. The only thing that seems to help is connecting via WiFi and not ethernet. I have no idea why but it does appear to make a difference (at least for me and many others)
6. It is mind boggling that Apple has not fixed this problem