2021 new gen Apple tv 4k Dolby Atmos Problems

[IraG]

I was on wifi when it started. Now hardwired in. 1Gbps service; gigabit ethernet; no bufferbloat issues. I refuse to accept its networking.

Perhaps I wasn't clear. I actually said the complete opposite of the Atmos problem being caused by network issues. What I said was that anything that prevents getting a 4K stream, such as a 1080p TV/AVR or a lower bandwidth network connection, should also prevent the Atmos problem. This was meant as one possible explanation for why there are people reporting no issues with Atmos. This could also explain the reports from those with Wi-Fi connections that don't have Atmos problems, which is counter-intuitive.

I believe there is a direct correlation between higher bandwidth video streams and the Atmos issues. In other words, if you have Atmos dropouts, you have a good enough internet connection to receive the highest bandwidth video stream. Perhaps an interesting experiment would be to intentionally limit the max bandwidth to the ATV4K, which can easily be done in the router. Connecting to 2.4 GHz might also do the trick.

 

[Robert D]

I was on wifi when it started. Now hardwired in. 1Gbps service; gigabit ethernet; no bufferbloat issues. I refuse to accept its networking.

Ok, so you experienced it on wifi as well? So a theory that it's an issue with the ethernet hardwired isn't possible.

It's just so strange how it's random dropouts. I think we did confirm that the worst show for the problem is Drive to Survive on Netflix. I was stunned how the audio dropped out before 10 minutes were up when I tested it. Usually I can go as long as 1 hour or more before it happens. For whatever reason, that show triggers it fast. Once it happened the 1st time, the audio dropped out very often afterwards. I've never had that on any other show or movie.

 

[Robert D]

Perhaps I wasn't clear. I actually said the complete opposite of the Atmos problem being caused by network issues. What I said was that anything that prevents getting a 4K stream, such as a 1080p TV/AVR or a lower bandwidth network connection, should also prevent the Atmos problem. This was meant as one possible explanation for why there are people reporting no issues with Atmos. This could also explain the reports from those with Wi-Fi connections that don't have Atmos problems, which is counter-intuitive.

I believe there is a direct correlation between higher bandwidth video streams and the Atmos issues. In other words, if you have Atmos dropouts, you have a good enough internet connection to receive the highest bandwidth video stream. Perhaps an interesting experiment would be to intentionally limit the max bandwidth to the ATV4K, which can easily be done in the router. Connecting to 2.4 GHz might also do the trick.

Some have had the atmos sound problem when streaming just music on Apple Music, so no video at all.

 

[IraG]

Ok, so you experienced it on wifi as well? So a theory that it's an issue with the ethernet hardwired isn't possible.

It's just so strange how it's random dropouts. I think we did confirm that the worst show for the problem is Drive to Survive on Netflix. I was stunned how the audio dropped out before 10 minutes were up when I tested it. Usually I can go as long as 1 hour or more before it happens. For whatever reason, that show triggers it fast. Once it happened the 1st time, the audio dropped out very often afterwards. I've never had that on any other show or movie.

I gave a very good explanation why Drive to Survive is so problematic. I suggest you re-read my recent posts.

 

[user 49813]

Perhaps I wasn't clear. I actually said the complete opposite of the Atmos problem being caused by network issues. What I said was that anything that prevents getting a 4K stream, such as a 1080p TV/AVR or a lower bandwidth network connection, should also prevent the Atmos problem. This was meant as one possible explanation for why there are people reporting no issues with Atmos. This could also explain the reports from those with Wi-Fi connections that don't have Atmos problems, which is counter-intuitive.

I believe there is a direct correlation between higher bandwidth video streams and the Atmos issues. In other words, if you have Atmos dropouts, you have a good enough internet connection to receive the highest bandwidth video stream. Perhaps an interesting experiment would be to intentionally limit the max bandwidth to the ATV4K, which can easily be done in the router. Connecting to 2.4 GHz might also do the trick.

Agree 100%. Was replying to a different comment.

 

[IraG]

Some have had the atmos sound problem when streaming just music on Apple Music, so no video at all.

Then I should have had the dropouts when I tested Drive to Survive at 1080p 50Hz, but I didn't. I believe that the reports of dropouts when streaming only Atmos music are due to the normal blanking of audio by the AVR when the audio stream changes formats. It does this to prevent potentially loud static/pops from reaching the speakers. I encountered that initial blanking when I tested Apple's Atmos music, and found it very annoying. I never did hear any Atmos dropouts after that initial blanking.

 

[ttocs]

For the record, my ATV4K is not wired, it's using WiFi.

 

[user 49813]

Then I should have had the dropouts when I tested Drive to Survive at 1080p 50Hz, but I didn't. I believe that the reports of dropouts when streaming only Atmos music are due to the normal blanking of audio by the AVR when the audio stream changes formats. It does this to prevent potentially loud static/pops from reaching the speakers. I encountered that initial blanking when I tested Apple's Atmos music, and found it very annoying. I never did hear any Atmos dropouts after that initial blanking.

I've noticed the audio "blanking" with various AVR's and Atmos sources (non-ATV). I tend to agree it is something different. Whenever I see discussion of "the issue" in other threads (especially macrumors and Reddit), people often conflate different audio problems with the actual one we're trying to get resolved.

 

[Robert D]

I've noticed the audio "blanking" with various AVR's and Atmos sources (non-ATV). I tend to agree it is something different. Whenever I see discussion of "the issue" in other threads (especially macrumors and Reddit), people often conflate different audio problems with the actual one we're trying to get resolved.

Yeah, I think you're right. Similar symptoms but different cause.

 

[ttocs]

Should be okay, but keep in mind that your ISP B/W is shared among all your internet devices. I assume you have a wired connection to your ATV4K Gen 2 and are not using Wi-Fi.

I use WiFi.

Speaking of Bandwidth, I am trying QoS for the first time and it's an eye opener. When monitoring the default settings which allows full bandwidth, no limits, and while watching Drive To Survive, the meters show bursts of 40-90Mbps for very short durations and 0Mbps for longer periods. A burst might be a couple seconds, and the waiting period that follows might be 4-5 seconds or even longer sometimes.

But when I limit Bandwidth to 30Mbps the situation reverses. No bursts, instead it's a more continuous rise to 27Mbps and hold for a few seconds, then a bit lower, then lower, then 0Mbps for a second or two, then the cycle repeats. All the while my processor shows 4K DV ATMOS with no audio drops - so far. There are times when the meter holds at 22-28Mbps for 6-8 seconds. The periods at 0Mbps are very, very short periods of time with the 30Mbps limit. I can see that if a network had more activity than mine that there would not be enough bandwidth to keep the ATV4K happy.

I was always under the impression that streaming would be more continuous, but it's not.

What this experiment is showing me is that it really is helpful to have the fastest speed just for situations when a number of devices might need to hit higher data rates. In my case tonight, it's just the ATV4K that's pulling anything measurable.

I would ask anyone who has lots of audio drops to login to their router and monitor which devices are accessing bandwidth for a while, get a feel for what's going on. Then, cutoff network access to other devices and watch an intensive show on ATV4K and monitor the meters to see how things go, and, see if anything improves. Then, maybe do the opposite. Limit the bandwidth to ATV4K and allow full access to everything else.

I'm 25 minutes into Drive To Survive S4:E1 with no audio issues, and the ATV4K is limited to 30Mbps.

I changed the res to 1080p. The bandwidth meter just quickly blips up to 50-70Mbps and goes back down to 0Mbps for 5-7 seconds, with a lot more 9-30Mbps blips mixed with some higher blips. The meter points to zero a lot with this resolution. I limited the bandwidth to 20Mbps and the meter still hits zero a lot, but also hangs at 18-20Mbps more often.

Any way you slice it, there have been no audio drops during any of this messing around tonight, and total time invested so far is over an hour.

 

[Robert D]

I use WiFi.

Speaking of Bandwidth, I am trying QoS for the first time and it's an eye opener. When monitoring the default settings which allows full bandwidth, no limits, and while watching Drive To Survive, the meters show bursts of 40-90Mbps for very short durations and 0Mbps for longer periods. A burst might be a couple seconds, and the waiting period that follows might be 4-5 seconds or even longer sometimes.

But when I limit Bandwidth to 30Mbps the situation reverses. No bursts, instead it's a more continuous rise to 27Mbps and hold for a few seconds, then a bit lower, then lower, then 0Mbps for a second or two, then the cycle repeats. All the while my processor shows 4K DV ATMOS with no audio drops - so far. There are times when the meter holds at 22-28Mbps for 6-8 seconds. The periods at 0Mbps are very, very short periods of time with the 30Mbps limit. I can see that if a network had more activity than mine that there would not be enough bandwidth to keep the ATV4K happy.

I was always under the impression that streaming would be more continuous, but it's not.

What this experiment is showing me is that it really is helpful to have the fastest speed just for situations when a number of devices might need to hit higher data rates. In my case tonight, it's just the ATV4K that's pulling anything measurable.

I would ask anyone who has lots of audio drops to login to their router and monitor which devices are accessing bandwidth for a while, get a feel for what's going on. Then, cutoff network access to other devices and watch an intensive show on ATV4K and monitor the meters to see how things go, and, see if anything improves. Then, maybe do the opposite. Limit the bandwidth to ATV4K and allow full access to everything else.

I'm 25 minutes into Drive To Survive S4:E1 with no audio issues, and the ATV4K is limited to 30Mbps.

I changed the res to 1080p. The bandwidth meter just quickly blips up to 50-70Mbps and goes back down to 0Mbps for 5-7 seconds, with a lot more 9-30Mbps blips mixed with some higher blips. The meter points to zero a lot with this resolution. I limited the bandwidth to 20Mbps and the meter still hits zero a lot, but also hangs at 18-20Mbps more often.

Any way you slice it, there have been no audio drops during any of this messing around tonight, and total time invested so far is over an hour.

Have you ever used it with hardwired ethernet?

 

[ttocs]

Have you ever used it with hardwired ethernet?

Doing that now, just wired it 20 minutes ago.

It now uses a higher ceiling for the bursts of download bandwidth used. On WiFi bursts usually top out around 90Mbps range when watching 4K DV 50Hz ATMOS, but wired it's a bit higher, just over 100-110Mpbs.

Nothing else on my network has been doing much since I've been looking tonight. I performed a speed test while watching Drive To Survive. One screenshot is one of the bursts for ATV4K (named ATV3), the other is the speedtest result. For the burst I had to react really quick because they only last for an instant.

 

[Robert D]

Doing that now, just wired it 20 minutes ago.

It now uses a higher ceiling for the bursts of download bandwidth used. On WiFi bursts usually top out around 90Mbps range when watching 4K DV 50Hz ATMOS, but wired it's a bit higher, just over 100-110Mpbs.

Nothing else on my network has been doing much since I've been looking tonight. I performed a speed test while watching Drive To Survive. One screenshot is one of the bursts for ATV4K (named ATV3), the other is the speedtest result. For the burst I had to react really quick because they only last for an instant.
View attachment 22742

View attachment 22743

Wondering if you will have the Atmos problem when it is hardwired. You were able to do it on your wi-fi with no problems, right? There are so many different cases on here that I keep getting them confused.

 

[IraG]

I use WiFi.

Speaking of Bandwidth, I am trying QoS for the first time and it's an eye opener. When monitoring the default settings which allows full bandwidth, no limits, and while watching Drive To Survive, the meters show bursts of 40-90Mbps for very short durations and 0Mbps for longer periods. A burst might be a couple seconds, and the waiting period that follows might be 4-5 seconds or even longer sometimes.

But when I limit Bandwidth to 30Mbps the situation reverses. No bursts, instead it's a more continuous rise to 27Mbps and hold for a few seconds, then a bit lower, then lower, then 0Mbps for a second or two, then the cycle repeats. All the while my processor shows 4K DV ATMOS with no audio drops - so far. There are times when the meter holds at 22-28Mbps for 6-8 seconds. The periods at 0Mbps are very, very short periods of time with the 30Mbps limit. I can see that if a network had more activity than mine that there would not be enough bandwidth to keep the ATV4K happy.

I was always under the impression that streaming would be more continuous, but it's not.

What this experiment is showing me is that it really is helpful to have the fastest speed just for situations when a number of devices might need to hit higher data rates. In my case tonight, it's just the ATV4K that's pulling anything measurable.

I would ask anyone who has lots of audio drops to login to their router and monitor which devices are accessing bandwidth for a while, get a feel for what's going on. Then, cutoff network access to other devices and watch an intensive show on ATV4K and monitor the meters to see how things go, and, see if anything improves. Then, maybe do the opposite. Limit the bandwidth to ATV4K and allow full access to everything else.

I'm 25 minutes into Drive To Survive S4:E1 with no audio issues, and the ATV4K is limited to 30Mbps.

I changed the res to 1080p. The bandwidth meter just quickly blips up to 50-70Mbps and goes back down to 0Mbps for 5-7 seconds, with a lot more 9-30Mbps blips mixed with some higher blips. The meter points to zero a lot with this resolution. I limited the bandwidth to 20Mbps and the meter still hits zero a lot, but also hangs at 18-20Mbps more often.

Any way you slice it, there have been no audio drops during any of this messing around tonight, and total time invested so far is over an hour.

Great post! Thanks for performing the experiment I suggested. You may need to drop the max limit if you still get the Atmos dropouts. The goal is to force a lower bandwidth 4K video stream that doesn't trigger the Atmos dropouts. I don't know how practical a workaround this would be for the Atmos problem, but it would be further proof that it is brought on by high bandwidth video streams. And it's interesting. Who knows -- maybe we know more about the Atmos problem than Apple.

What you are seeing on the router's bandwidth meter is going to average out to the stream's bandwidth. Without the limit, you will get high bandwidth bursts as the streamer is simply trying to keep its buffer full, and I expect that short bursts are much more efficient than a slow, steady stream of data. Not capping the maximum bandwidth will allow your videos to start more quickly, and more quickly refill the buffer if the connection is spotty.

Other devices on the network will not have any effect on the Atmos dropouts, unless they end up lowering the available bandwidth to the ATV4K and forcing it to a lower bandwidth stream, in which case it would prevent the Atmos dropouts, and you would likely see a drop in video quality. But this should never happen in households with 1Gb internet unless someone is doing a lot of downloading.

By limiting the available bandwidth to the ATV4K in the router, you are doing this in a controlled manner that should not noticeably degrade the video quality. Making more bandwidth available to the ATV4K makes matters worse, since the ATV4K will receive the highest bandwidth video stream available, and that is what triggers the Atmos dropouts.

 

[ttocs]

Wondering if you will have the Atmos problem when it is hardwired. You were able to do it on your wi-fi with no problems, right? There are so many different cases on here that I keep getting them confused.

On WiFi, with many hours of ATMOS, I only had one 2 second audio drop.

Wired, watching Drive To Survive. One ATMOS drop in each of two episodes. Then while watching a third episode I stopped, checked some things, then began playing again and got 5 audio drops in 15 minutes. My processor has OSD so I can see what's going on on-screen. The first photo is an audio drop when it went from ATMOS to DD Surround, the second photo is when it went back to ATMOS. You can see that the incoming audio dropped from DDTrueHD/ATMOS to PCM 7.1/DD Surround (incoming/outbound). I ran speedtest on the ATV4K and it was the same as speedtest on the router.

 

[ttocs]

Great post! Thanks for performing the experiment I suggested. You may need to drop the max limit if you still get the Atmos dropouts. The goal is to force a lower bandwidth 4K video stream that doesn't trigger the Atmos dropouts. I don't know how practical a workaround this would be for the Atmos problem, but it would be further proof that it is brought on by high bandwidth video streams. And it's interesting. Who knows -- maybe we know more about the Atmos problem than Apple.

What you are seeing on the router's bandwidth meter is going to average out to the stream's bandwidth. Without the limit, you will get high bandwidth bursts as the streamer is simply trying to keep its buffer full, and I expect that short bursts are much more efficient than a slow, steady stream of data. Not capping the maximum bandwidth will allow your videos to start more quickly, and more quickly refill the buffer if the connection is spotty.

Other devices on the network will not have any effect on the Atmos dropouts, unless they end up lowering the available bandwidth to the ATV4K and forcing it to a lower bandwidth stream, in which case it would prevent the Atmos dropouts, and you would likely see a drop in video quality. But this should never happen in households with 1Gb internet unless someone is doing a lot of downloading.

By limiting the available bandwidth to the ATV4K in the router, you are doing this in a controlled manner that should not noticeably degrade the video quality. Making more bandwidth available to the ATV4K makes matters worse, since the ATV4K will receive the highest bandwidth video stream available, and that is what triggers the Atmos dropouts.

Are you suggesting I use QoS in the router to limit the bandwidth like I was experimenting with earlier tonight while still using WiFi? If so, what level would you suggest for using Ethernet Wired?

edit: I tried 60Mbps and got a drop within minutes.
Set it for 30Mbps and after about 10 minutes, no drops. The bandwidth is staying mostly up around 29Mbps, but goes between 8Mbps to 29Mbps, and rarely drops to 0Mbps. So the stream is more constant.

 

[ttocs]

If limited bandwidth controlled by the router helps, this might mean that the wired connection on the ATV4K is an old spec that hasn't been updated in some way. But it measures as fast as the WiFi, so throughput is not the problem.

At 30Mbps the video still looks great.

 

[IraG]

Are you suggesting I use QoS in the router to limit the bandwidth like I was experimenting with earlier tonight while still using WiFi? If so, what level would you suggest for using Ethernet Wired?

You should use the same limits for Wired as for Wi-Fi. Only difference is wired is more consistent as it isn't subject to congestion or interference like Wi-Fi. I would start at 30Mbps for the 4K 50Hz Drive to Survive. If you still get Atmos dropouts, lower it in 2Mbps increments until the dropouts stop.

You are trying to find a limit where the streamer can't keep its buffer full, and has drop to a lower video bandwidth. It makes no difference if you use a wired or wireless connection. There is nothing wrong with either. The problem is the ATV4K Gen 2 can't handle the higher bandwidth video without introducing errors in the MAT 2.0 Atmos stream. It should have nothing to do with the network connection. I guess I should go test Drive to Survive on Wi-Fi to double-check, but I am sure I tested Wi-Fi before and got the Atmos dropouts.

 

[Robert D]

Are you suggesting I use QoS in the router to limit the bandwidth like I was experimenting with earlier tonight while still using WiFi? If so, what level would you suggest for using Ethernet Wired?

edit: I tried 60Mbps and got a drop within minutes.
Set it for 30Mbps and after about 10 minutes, no drops. The bandwidth is staying mostly up around 29Mbps, but goes between 8Mbps to 29Mbps, and rarely drops to 0Mbps. So the stream is more constant.

And you're still able to get dolby vision picture, just as good as when the stream is not capped?

I guess the Apple tv is unable to deal with a stream that has a bitrate too high? Perhaps Apple could build something into the OS to deal with it? Do we think this is a hardware limitation?

 

[Robert D]

If limited bandwidth controlled by the router helps, this might mean that the wired connection on the ATV4K is an old spec that hasn't been updated in some way. But it measures as fast as the WiFi, so throughput is not the problem.

At 30Mbps the video still looks great.

At 30 mbps it's still Dolby Vision? I wouldn't think that there are different degrees of Dolby Vision. Isn't it either Dolby Vision or not?