Netflix Dolby Atmos problems with new Apple TV 4k

I'm made of the earlier posts on this thread and came back to see if there was a fix. I've been using the built-in GoogleTV apps on my Sony TV and Atmos works perfectly over eARC. However, I prefer the AppleTV's UI so I just updated my AppleTV 4K Gen 2 to 15.4 and tried again. That update had no effect on the problem, and possibly made it worse. The AppleTV is connected to the Media Player input on my Marantz 8500HA (it's an HDMI 2.1 input) and playing Atmos Music from Apple Music pretty much doesn't work at all anymore. It glitches after a few seconds. If I reboot the box, I can watch an Atmos show for a bit, but it usually glitches within 20 minutes and then becomes unwatchable.

Since I've been enjoying Atmos Music and the AppleTV is the only way to get it, I swapped the box for my Gen 1 Apple TV. That's a nuisance because I have to log back into all of the apps that timed out while it was unplugged -- but it plays Atmos Music perfectly. It also has Dolby Vision, which I didn't remember it having (thought that was a Gen-2 feature). The only downside is that it's noticeably slower than the Gen 2, especially when scrolling around, and doesn't have the new remote (but I use my TV remote anyway which is actually better than even the new AppleTV remote).

I hope Apple gets their act together and fixes this problem, or if it turns out to be a hardware issue, somehow makes us early adopters whole (I bought it the week it came out). At the moment it's useless.

It's not an early adopter issue. I exchanged a preorder Gen 2 in December, also thinking it could be a problem with the initial production run that was later fixed, and there was no difference after updating to 15.3. The installed 14.7 also had the Atmos problem, but 15.3 was an order of magnitude worse (more frequent). I would have left it on 14.7, but Apple gets rather obnoxious with the constant nagging to update, and I had a Gen 1 as a fallback.

Everyone I guess is entitled to their own theories/speculation as to the root cause of the problems.

Mine is that for people with complicated setups (e.g. lots of speakers including height speakers) the ATV 4K Gen 2 is just being pushed too hard and components are being asked to do more than they can handle in a very tight space…maybe things are overheating or there is interference of some sort between the components all running at their maximum limits.

Dont forget that the ATV 4K is doing a lot more processing than a standard streamer that just passes the uncompressed input to an AVR; the ATV 4K has to uncompress the input itself instead of letting the AVR do that, it has to also do all the special audio computations for Apple AirPods, it has to handle HDMI 2.1, and it also has its power supply inside that tiny space.

Maybe it just isn’t capable of doing all it is trying to do for complicated setups.

A few things for you to consider:

1) The ATV4K isn't doing any extra work for a system with lots of speakers compared to a simpler 5.1.2 Atmos system, such as mine, or an Atmos soundbar. The receiver/soundbar is decoding the Atmos metadata and distributing it among the speakers.

2) I quickly ruled out a thermal issue when I had the Atmos problem soon after plugging in the ATV4K, so it had no time to overheat.

3) I am well aware that the ATV4K is doing more than most streamers. Apple chose not to support bitstreaming on these devices, which would have avoided the Atmos problems. My hypothesis has been that the Gen 2 problem is introduced in the creation of the MAT 2.0 Atmos metadata, which would explain why no other audio formats are affected. I have speculated why this might be happening on other posts.

4) If the problem were that the ATV4K is being pushed too hard, then the Gen 1 units should have been the first to suffer the Atmos issues, since the A12 Bionic is significantly more powerful than the A10X Fusion.

First had atmos audio drop outs on Netflix several weeks ago. Atmos has been working fine for more than a year. Last night wile watching Drive to Survive (~50 min) audio dropped out about 10 times. No audio for 3 seconds or so. Netflix seems to be the only app that does this.

Updated Tuesday to 15.4 and no better, so not caused or helped by 15.4. Restarting Netflix app seems to do nothing. Restarting Apple TV also not much help.

You are assuming that there’s no logic in TVOS that checks the hardware version it’s running on and then does extra processing if it sees it’s a Gen2…I am thinking it might do a lot more work on the Spatial Audio side on the more powerful Gen 2.

I am thinking the issue is more likely related to hardware design than purely software, and that’s why this hasn’t been fixed by now.

if the fix requires a change to the hardware it would be very expensive and possibly restore in recalls and bad publicity.

Then explain why most users are not experiencing any issues. I’m not with Apple TV 4K 2021->Denon AVR-5960H->Sony XR-65X90J. No dropouts at all, ever, not even while playing Spacial Audio on Apple Music. If it’s a hardware design issue, meaning Apple engineers are incompetent, then the issue should be affecting a lot more than the few in this thread.

This isn’t a hardware issue. It has to be purely software. I have tried 3 different receivers (multiple brands even), 2 Apple TV’s, multiple hdmi cables, and the issue persists for me inside of Netflix. The support staff at Apple have even acknowledged that there is some software issues the engineers are aware of and are working to fix. Was just updated on this yesterday from my advisor.

You are correct -- I am assuming that Apple didn't invest any time or money in upgrading the software for the modest speed bump in the A12. I believe all they did was spin a new board to accommodate the faster chip. I believe Apple assumed the same software would work on the new hardware, but overlooked some subtle difference that is causing the Atmos issue. I don't believe Apple really cares about the Apple TV product line, since it isn't a big seller.

As I posted, I replaced the 2021 AppleTV 4K with TVOS 15.4 that fails to play Atmos pretty quickly with my original gen-1 version that's still running TVOS 14.7. That plays Atmos fine. However, it's nagging me to install an update. Does anyone have 15.4 on the original AppleTV 4K and does it have the Atmos problem?

I'm concerned that the Atmos problem may have been introduced after 14.7 on both Apple TV boxes, but I'm also concerned I might not have the latest version of the apps Like Netflix on this box and that might become a problem. Hulu in particular was flaky until I uninstalled and reinstalled the app. Lots of spinning.

I have no idea why Apple is taking so much time to fix this problem unless it's really intractable. My 2021 box just sits on the shelf for now waiting for a fix.

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).

lkrupp wrote:

Then explain why most users are not experiencing any issues. I’m not with Apple TV 4K 2021->Denon AVR-5960H->Sony XR-65X90J. No dropouts at all, ever, not even while playing Spacial Audio on Apple Music.

[...]

No doubt this issue is hard to nail down... here's just one example of a 2nd-gen ATV4K in a home theater system without any Dolby Atmos-related issues. @Golfergb just reported experiencing Atmos audio drop-outs with a gen1 ATV4K, whereas most others with gen1 ATV4Ks on this thread, including myself, never have.

I realize the news that many others are cheerfully enjoying troublefree Atmos surround sound through their ATV4K gen1&2 devices is little comfort to folks who are experiencing issues. But hopefully it can raise awareness about how challenging it is for a vendor like Apple to troubleshoot, let alone fix, problems like this within multivendor AV systems where every dern supposedly interoperable component has a bunch of settings that are often misunderstood by those who buy them.

FWIW, this thread made me curious about reports of Dolby Atmos issues that don't involve Apple TV devices, so I did a Google search for Atmos issues excluding the word "Apple". Nearly 10 million results. Of course it's likely that many of these results represent complaints to AV component vendors involving unreferenced ATV4K devices (Atmos is a high-end home theather option and Apple TV 4K is the high-end streaming media box). But most of the results in the first few pages do appear to involve competing devices.

Like most of us, I'm an end user who's clueless about the nuanced hardware and software details of engineering interoperable AV components. Perhaps we should all be complaining to Dolby? Of course, Dolby's business model is all about licensing technology to OEMs, so... they're not really setup to listen to all of us end-users :-).

Yes, the AppleTV 4K decodes the bitstream and then sends a Dolby MAT overlay. Since it's linear PCM over HDMI out of the AppleTV, that's far more bandwidth than the compressed Dolby Digital Plus bitstream that's used to deliver Atmos from Netflix, HBO Max, Disney+, and even AppleTV+ plus. However, with the "Apple TV 4K uses a high bandwidth form of Dolby Atmos that doesn’t work over ARC connections." quote, I wonder if it would work over eARC, since that supposedly support uncompressed multi-channel Dolby TrueHD and DTS-HD. I have not tried connecting the AppleTV directly to my TV to see if the Atmos problem occurs over eARC, but it might be an interesting experiment. Assuming it can deliver Atmos over eARC at all.

A passthrough option is the way to go -- I'd rather have my top-of-the-line Denon AVR decoding the signal than the AppleTV.

I tried eARC with my ATV 4K and there were fewer drops/static etc. with Atmos content but they did still occur.

One reason I bought the ATV 4K was so I could plug it into my Denon and be able to see the volume and audio overlay info that the Denon displayed on the screen, so using eARC wasn’t any better than just using the builtin LG TV apps...actually worse since they didn’t have any audio drops.

I was also hoping the ATV 4K would fix the annoying dropped frames I got with my Roku (which it did)….but the ATMOS audio problems were far more annoying than the occasional dropped frames from the Roku.

A lot of people would prefer to have the ATV4K support bitstreaming so that their AVR could do the Atmos decoding, but we are obviously wrong because the Apple way to do the Atmos decoding and then reencoding into LPCM + MAT 2.0 Atmos metadata must be the right way. There are other reasons for doing it the Apple way, but for the highest quality, I would rather have my Denon do what it was designed for, skipping the extra decode/encode step, and not having to deal with the Atmos sloppy seconds from the ATV4K.