Netflix Dolby Atmos problems with new Apple TV 4k

you shouldn't focus too much at the 50Hz. I assume you get the 50Hz info from your AVR or TV. I've read that dts is a 25Hz version on Netflix -they do anything to keep the data rate low. The ATV doubles it up to 50 (tested it on Prime with a Firestick vs. ATV a while ago). I don't know if xcode would show the real incoming frame rate, I don't have a Mac and won't buy one just for this, my PC's running Linux.

The next test could be to force the ATV to output 25Hz (1 Hz more should take that effect). Next could be another Atmos content e.g. from Apple+ (didn't have a dropout myself, from others seldom reported) with forced 60Hz output.

The Denon app tells me that DtS is 50Hz. I have the ATV4K set to match Frame Rate, so I don't see why it would double 25Hz to 50Hz. It makes sense that DtS would have been produced at 50Hz due to the fast racing action, and that Netflix would stream that 50Hz version to us. I can't believe that Netflix would compromise the video quality for the very few shows that are 50/60Hz. If DtS were converted to 25Hz, I would expect it to be pretty choppy looking, and it isn't. I believe forcing DtS to 25Hz would still have dropouts, as I believe it is the frame rate and bandwidth of the stream coming into the ATV4K that matters, and for now I believe it is a 50Hz stream. I agree that forcing 25Hz is a worthwhile test and would give us another data point.

I just tried forcing 25Hz out of the ATV4K and the menu/home screens were 25Hz per the Denon app, and noticeably choppy. When I played DtS, the video was smooth and the Denon app said it was 50Hz, which I expected as I have match Frame Rate ON. When I previously tested DtS forced to 1080p 50Hz (match Frame Rate ON), I had no dropouts. Before it was pointed out to me that DtS was 50Hz, I already believed DtS was higher bandwidth than other shows due to the fast action/cuts.

Forcing 60Hz out for a lower frame rate video source will just cause the ATV4K to telecine the video, where it repeats some frames as required to match the NTSC video format frame rate of 30Hz (29.97Hz) or 60Hz (59.94Hz). With match Frame Rate ON, the telecine process is not performed.

I have had some dropouts on ATV+ shows such as Invasion and Foundation, but never on Servant. Again, I believe that is due to video bandwidth, with Servant being relatively low bandwidth -- nothing moves much in that show.

Like mostly everyone here I’m having the same issues with the AppleTV4K 2nd generation in a 5.1.2 setup and Yamaha 2060 trying to stream drive to survive with atmos. I have no other problems with atmos on other streaming apps.

I swapped my 2nd gen with my first gen appleTV 4K into my setup and I haven’t had a single issue yet so it’s clearly a 2nd gen issue.

For what it’s worth , my 2nd gen was still under warranty so I swapped it and I’m waiting for the replacement. I’ll report back if it fixed anything.

Your Gen 2 replacement will have the same problem. I have suggested several workarounds, such as using a Wi-Fi connection (seems to reduce dropout frequency significantly), and forcing the output to 1080p, which depending on your seating distance, TV 4K upscaling quality, etc., may be the best option and should completely eliminate the dropouts. I go into a lot more detail in recent posts.

You should also keep your replacement on tvOS 14.7 (if that is what it currently ships with), if you can deal with Apple's constant nagging to update. I found 15.x had an order of magnitude more dropouts than 14.x. My Gen 1 also never had any Atmos dropouts, even when I tested with DtS.

Interesting. I was never able to make it through an episode of DtS without dropouts until I tested it with the ATV4K output set to 1080p. I only had 1 dropout on DtS at 4K 50Hz on Wi-Fi, and countless dropouts on 4K 50Hz DtS wired.

If DtS at 4K 50Hz has the most dropouts, and all other 4K 24Hz content has significantly fewer dropouts, it seems reasonable that a 1080p 24Hz or 50Hz stream, which is lower bandwidth than 4K content, would have very few or no dropouts. I don't believe there is anything inherently different between these test cases other than video bandwidth.

I was very skeptical of the reports that a Wi-Fi connection had significantly fewer dropouts than wired, so I didn't test that until recently. To my surprise, I found that DtS had significantly fewer dropouts on Wi-Fi. I can't argue with the results. Fozzy1969 on this thread tested this for himself and came to the same conclusion, and I know of others who had similar results.

Perhaps there are other variables in play that affect the test results, such as performing a System Restart before each test.

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.

Good post.

I agree that forcing 1080p isn't for everyone. I even said that seating distance, TV 4K upscaling quality, etc., are all factors. I sit 7 feet from a 75" Sony 940E, so I am in the range where 4K makes a difference over 1080p. If I were 10 feet from the screen, a figure I suspect is a more typical viewing distance, I would not be able to see the difference. There are many TV viewing distance charts online to help people people determine if 4K makes a difference. I also have other streaming options that do not have any issues, such as my Gen 1 ATV4K, Roku Ultra, and Sony TV apps (my 2017 Shield doesn't support DV, so not an option), so there would be no reason for me to force 1080p.

I would appreciate if you could test my recommendations (forced 1080p, Wi-Fi) to see if you get similar results, since we have similar setups other than my Sony 940E TV and Denon AVR-X4300H are about 5 years old. I find it curious that some people mirror my results, while others don't.

Btw, I have ruled out DV as a factor. The first season of DtS is not streamed in DV, while season 2 up are. DtS S01E01 is my go-to test episode as it has the most frequent and consistent dropouts due to it being 4K 50Hz. I agree that your observation of the dropouts only at the start of two "The Essex Serpent" episodes is curious. Perhaps that is just random chance. Other than DtS, I find the dropouts to be too infrequent to make meaningful generalizations. I have watched some shows for many hours -- even complete seasons -- without dropouts. I never heard a dropout in "Servant", for example, and I attribute that to low video bandwidth.

I’m having a similar issue. I can’t tell if it’s related to what others are experiencing or not. I have a Vizio m51a-h6 Soundbar, which is a 5.1 setup with a subwoofer and rear speakers. The sub/rears have been having frequent audio drops but only with my Apple TV (4K Gen 1). I don’t lose center channel audio, though. I tried the suggestion of switching off Atmos or to Dolby 5.1, and those seemed to work for a time but now it’s occurring even with regular 5.1 content. Has this version of this glitch happened similarly for anyone else? I’m still trying to determine the cause of this, and can’t tell if it’s this same glitch or another issue. It does only seems to occur with my Apple TV, though. And it only began in the last week.

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.

Speculative: it depends on how Apple has the ethernet port interacting with the CPU. Maybe the ethernet port is using some PCIe lanes that another component is - who knows for sure. Maybe the wifi doesn't.

Be funny if - they had the Ethernet port lane sharing with bluetooth (keeping BT separate from wifi?) and its the BT communication that's causing the bobble.

With Apple who knows.

Only thing that makes Apple fix things is negative press - start sending it to Linus or some other YouTuber.

I'll first try using just WiFi with the AppleTV 4k. I'm not watching that many Atmos shows right now and am caught up on "The Essex Serpent" so it'll be a few days until the next episode is released.

The last episode of "The Essex Serpent" that I watched over the weekend had two of the chopping dropouts: the first within the first few minutes of the program, and the second about half-way through. I hadn't rebooted the box in a few days (keep forgetting). It's also possible that I paused the program for a bit and the dropout happened not long after I resumed the program. I sometimes wonder if pausing might allow the connection to catch up and overflow some buffer. It's all just speculation though.

The theory about buffer overflow with a fast wired ethernet connection is interesting. I have 200/10mpbs service, which is really 230/12 or so. I checked my WiFi speed with my iPhone 12 Max Pro and it's identical: 230/12 so if a buffer is going to overflow, it'll overflow then too unless the different port or processing matters.

If it keeps happening, I'll try the 1080p trick. In my case, though, I'd probably rather turn off Atmos in favor of 5..1 than give up 4k.

Sounds like your Wi-Fi and Ethernet speeds are going to be very close, so it would be an interesting test. You can install Speedtest right on your ATV4K if you want to check. When I tested DtS on Wi-Fi versus Ethernet, I measured 300/30mbps on Wi-Fi and only got one dropout, and 700/30mbps on wired and got lots of dropouts. I had no dropouts at 1080p, but I would only recommend that if your seating distance is too far for 4k to be of benefit. If you do any testing, DtS produces the most consistent and frequent dropouts due to it being 4k 50Hz.

Well, I am having this issue as well. I had no problems with Netflix until I updated to 15.5.1. Now I am watching season four of stranger things and the audio dropouts happen every few minutes. The only way I can fix the issue is to let it run and maybe the audio will come back or is to rewind 10 seconds and let it play and it will play with sound. But it is super annoying and I have not had this issue until updating to 15.5.1.I guess there is no way to revert back to the prior version of the operating system but this is truly annoying.

Turning off Dolby audio in settings solves the issue. My cabling and all else is fine. This didn’t start until I updated to 15.5.1. I’ve only tried watching Netflix and Stranger Things 4, pt. 1 and only through the ATV 4K 2021.

Also, does this happen with the Netflix apps built into a TV or just through the Apple TV 4K? I have a Sony A80J I purchased in November.

And by the way, does Apple know about this issue? I have no idea how to report it to them.

Yes, I will try that. But I feel I shouldn’t have to. And I have some reasons why I prefer Ethernet. This just started for me after 15.5.1 was installed, so Apple broke this. They should fix it. How do we let Apple know about this?

Is there a way to notify apple of this problem? I know they do not review these support entries so I would like to add my name to any complaint site that shows this is an issue. I paid way too much for this device to have to use work around in order to watch a show the way I want to watch a show.

But again, thanks for your help.