So the reboot seemed to "fix" the issue long enough to watch The Adam Project on Netflix? The latest OS seems like it gives you more trouble than what I'm having with my older one.
Which service has Spider-Man?
2021 new gen Apple tv 4k Dolby Atmos Problems
- Thread starter Robert D
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Help Support MartinLogan Audio Owners Forum:
Which service has Spider-Man?
I hope this thread has helped some to make the decision not to get an Apple tv. Now if you dont watch in Atmos, then it's great. I have a feeling that the number of housholds watching in Atmos is relatively small, hence the little attention Apple gives to this problem. My gut feeling is that they have not done a thing to fix it.
JLasher22443
Well-known member
That is Apple's Movies that you purchase and have stored in your Apple Account. I've never had an issue with movies purchased from Apple.
Ok, but when streaming their shows you have? Ive had troubles with Atmos streaming on there too but not as bad as Netflix. Thats just watching shows on the Apple TV + service. I had issues with See and For All Mankind.
JLasher22443
Well-known member
Nothing as of late only on Netflix.
This week I've watched six hours, so far, of NETFLIX ATMOS/DV streaming from a Gen2 TV4K with no issues. I never noticed audio dropouts before while streaming ATMOS on NETFLIX, but this week I've paid particular attention so I've been keen to look out for any audio dropouts and messed up audio, but have experienced none so far. Also, no pops/ticks, which is something I used to experience when navigating menus or going from one app to another with TV4K, and I've listened to quite a bit of music this week as well but music is always only two channel for me.
The provider is Xfinity. I only paused a few times, otherwise I just watched the shows straight through.
My system is setup for 7.1.4. To those of you having problems, do you have 7.1.4, or a different channel count? I've read that the TV4K can provide 7.1.4.
TV4K settings:
4K Dolby Vision 60
Match Content: Range & Frame Rate
Audio Format: Auto, ATMOS Available
The provider is Xfinity. I only paused a few times, otherwise I just watched the shows straight through.
My system is setup for 7.1.4. To those of you having problems, do you have 7.1.4, or a different channel count? I've read that the TV4K can provide 7.1.4.
TV4K settings:
4K Dolby Vision 60
Match Content: Range & Frame Rate
Audio Format: Auto, ATMOS Available
I'm using 7.1.4. That's 7 channels around and 4 on the ceiling. 1 sub.
So 2 fronts. 1 center, 2 rear sides, 2 rear backs, and 4 atmos in ceiling.
Relatively new Marantz 11 channel Atmos receiver. Using ethernet on fiber network. 600 mbps, tested.
user 49813
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5.1.2 here for now. But, the ATV should support the max number of channels for home-based Atmos (which if I recall correctly is technically 24.1.10, despite no products in the consumer market to decode that many). The Atmos decoder takes care of that, so really limited only by your processor, with nothing inherently limiting in the AppleTV device. Which is kind of what makes Atmos so special; no need to transmit discrete channels, just the metadata.
Interesting you're not having issues; is that with the Emotiva in your signature? The reported issues of the problem seem to be across a wide variety of equipment (from reading various threads across the internet) including soundbars, but I wonder if some manufactures are immune. Maybe the affected products all share the same HDMI chips which are more sensitive to whatever the ATV fault is. I have no issues with the ATV4k gen 1, and tvOS <15 seemed to be (mostly) free of it on the gen 2's. But, it's definitely an Apple problem.
Watched some Netflix content last night, without rebooting first, and had 3 occurrences in the first few minutes. Did a restart and made it through about 3 sixty-or-so-minute episodes before getting another occurrence. Wonder how bad it would be if the Netflix app started implementing the native tvOS video player instead of their own; could this be a common thread for those affected?
As I posted previously, I'm also on Emotiva (though a different model in that "family" of processors) and not seeing the drops on Atmos-encoded source material over AppleTV.
On a whim I decided to try the new TVOs, and it seems to have tamed a number of the clicks and pops when changing audio modes. There still are some, but they're much quieter.
On a whim I decided to try the new TVOs, and it seems to have tamed a number of the clicks and pops when changing audio modes. There still are some, but they're much quieter.
Im going to stick with my old OS and apps for now, wait until you guys get better results.
Yes, I use a Emotiva XMC-2. The Emotiva RMC/XMC-2 processors use chips that are different from quite a few other processors, so, there could be something to how a processor chip difference might relate to this issue with TV4K ATMOS dropouts. But. Since Apple seems to think there's an issue, then it is probably more likely to be something amiss with the their product.
Like a lot of issues with A/V products these days, there are a lot of pieces to the puzzle, and some pieces fit better than others.
As an aside, I don't usually have CEC enabled on my processor, but I did enable it last night just to see if there might be some difference. After a 40 minute show last night, and now a 1-1/2 hour show tonight, I'm still not having any audio dropouts. But I am having more pops when I was attempting to find a show that I would be interested in watching tonight, but kept finding shows that were listed as being ATMOS on NETFLIX, but when they started, they were not, so when the audio stream changed from one mode to another is when some pops showed up. I'm pretty sure this is just coincidence, and not related to whether or not CEC is enabled. Too early to tell for sure though.
Bottom line, I'm not having audio dropouts with ATMOS content from NETFLIX.
I'm having dropouts yet I've never heard these audio pops when switching shows or on a menu. My pops and dropouts only occur during an Atmos show, otherwise mine performs well with no audio problems. Can watch dolby 5.1 ad infinitum and no issues. I'm watching The Last Kingdom now and it's just 5.1. No issues and I'm almost done with it, 10 episodes.
It does seem like the brand of equipment that the Apple is streaming to has some sort of impact if your Emotiva is ok.
How many hours of Atmos have you streamed on it with no events? There were time spans for me where I could watch 6 hours or more and not have a single hiccup. It all seems random, which makes me think it must depend on the streaming somehow. I can watch a scene several times and the audio is different each time. The sound problems don't depend on the point in the show.
Some nights seem worse than others. When I have a problem, I check the ethernet speed on my device and it's always between 500 and 600 mbps. Then i checked buffer bloat and got a good or better rating. I'm wondering if maybe my internet provider is throttling some services? I asked the techs on the phone and they all said no, that's not done. Maybe Netflix itself gets too congested and has trouble? If that is the case, I'd think there would be other streaming problems other than just Atmos. Then there is the matter that the Atmos sound problem happens on Apple tv+ as well.
Next time I watch Atmos content I will try to remember to reboot the Apple tv first before watching. See if that helps.
It does seem like the brand of equipment that the Apple is streaming to has some sort of impact if your Emotiva is ok.
How many hours of Atmos have you streamed on it with no events? There were time spans for me where I could watch 6 hours or more and not have a single hiccup. It all seems random, which makes me think it must depend on the streaming somehow. I can watch a scene several times and the audio is different each time. The sound problems don't depend on the point in the show.
Some nights seem worse than others. When I have a problem, I check the ethernet speed on my device and it's always between 500 and 600 mbps. Then i checked buffer bloat and got a good or better rating. I'm wondering if maybe my internet provider is throttling some services? I asked the techs on the phone and they all said no, that's not done. Maybe Netflix itself gets too congested and has trouble? If that is the case, I'd think there would be other streaming problems other than just Atmos. Then there is the matter that the Atmos sound problem happens on Apple tv+ as well.
Next time I watch Atmos content I will try to remember to reboot the Apple tv first before watching. See if that helps.
As I've noted previously, I hadn't ever noticed any audio dropouts before this week. But this week I've been paying special attention to everything and have not had any dropout event in over 9 hours of NETFLIX ATMOS streaming. I'll keep at it though, as I've been thoroughly enjoying the Drive To Survive, which is very well produced!
When driving Apple headsets, it bypasses the whole MAT thing, as it all locally routed inside the ATV. MAT is strictly an HDMI related thing.
When driving Apple headphones, the ATV routes the decoded DD+ Atmos stream to the Apple Spatial Audio renderer, which then performs binaural mapping along with headtracking (keeping the sonic 'image' centered to the screen as you turn your head) and sends that 2ch signal over Bluetooth to the headset(s).
This is much like the A16 in terms of audio rendering chain , the base DD+ with Atmos extensions is handed to a base renderer, which will then render into a 5.1.2 all the way to a 7.1.4 set of virtual speakers (the stream indicates how it was mixed). Once the virtual speakers have their 'signals', the Spatial Audio processing takes that and generates a binaural version, and integrates head tracking feedback as well.
The A16 adds two more levels, which are the speaker/room modeling performed during the initial render, and applying personalized HRTF and headphone EQ (optional) when generating the binaural signals. It is these two that elevate the A16 into a league of its own.
I kind of think Apple has a global license that gives them a lot of flexibility. That said, it is likely based on a per TVOS /iOS instance, with zero connection to accessories like headsets. The renderer requiring licensing rights is a part of those OSs.
The headsets have no 'spatial' HW nor code beyond the leveraging of the BT triangulation of earcups to BT base device used for head tracking inputs.
Much like the A16 can work with any headset, one just clips a wired head tracker to the headband of the cans. All the decoding/rendering/modeling happens in the box.
Finally, yes, the root issue does seem to be the MAT 2.0 stream handling when traversing an HDMI link.
Since that link runs at a huge number of different speeds (related to the video signal format), not surprised there are some corner cases where timing bugs have crept in.
I'll have more to say later, but simply running 4K HDR chroma at 4.2.0 vs 4.2.2 (a fast link required) seems to induce the issue more frequently.
Apple can't be the only company using MAT on their devices. Why aren't we seeing this on every device that uses MAT? Haven't heard of it happening on other streamer brands. Do 4k disc players use MAT when they bit stream to the AV receiver? Think I have that terminology right. When I play 4k discs with Atmos on them I have to stream it to the receiver raw and then have the receiver decode the Atmos. The player isn't capable of doing Atmos. It never has this problem.
My Amazon Firestick never had it either. Just trying to understand. I guess Apple just hasn't figured out the proper hardware/software combination to deal with MAT?
I am sure some here have noticed that I have been pointing my finger at the MAT 2.0 encoding/timing as the root cause of the Atmos problem for quite some time now. I believe Apple is the only major player taking this approach to Atmos support. I believe all the disc players bitstream to the AVR.
A large part of why I have posted my hypotheses about the Atmos problem, both here and on the Apple support forum, was that I naively hoped that some of it might trickle up to Apple's engineers, and contribute in some small way to the resolution of the Atmos problem. I am also an electronics engineer by profession and enjoy troubleshooting.
So, how about the other streamers like Amazon Firestick and Nvidia Shield? Don't they use the MAT 2.0, or is it bitstream too?
Well it happened today. After streaming the Indycar race on Peacock, I switched over to NETFLIX to show my buddy the Drive To Survive show. We watched about ten minutes and I started skipping around to specific parts. After a few times doing this, the sound stopped for a couple seconds, the processor displayed a different audio mode, then back to ATMOS, then the sound started up again. So far that's the only instance of lost audio.
Mostly going from an article I read months ago, I believe other streamers do not use Dolby MAT 2.0. Here is the article: The Ultimate Dolby Atmos Guide
The Shield bitstreams. I don't know about the higher end Amazon devices or the latest Roku Ultra, but I doubt they use Dolby MAT 2.0. I expect they take the cheaper approach to supporting Atmos, which I assume is to pass it through to the AVR.
The Shield bitstreams. I don't know about the higher end Amazon devices or the latest Roku Ultra, but I doubt they use Dolby MAT 2.0. I expect they take the cheaper approach to supporting Atmos, which I assume is to pass it through to the AVR.
Wow, I hope that's true. I think if Apple doesn't fix this by summer I will get an Nvidia Shield. I've got a high end gaming pc and could stream games too. Using a rtx 3080ti.
