If it drops to a lower video bandwidth, wouldn't it at some point lose Dolby Vision?
2021 new gen Apple tv 4k Dolby Atmos Problems
- Thread starter Robert D
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I did some testing this evening. I started with my ATV4K Gen 1 (tvOS 15.3) on a wired connection and played a complete episode of Drive to Survive without any Atmos dropouts. No surprise there, as I have never had an Atmos dropout on my Gen 1. I just thought I should test it on the most problematic 4K 50Hz Atmos program I know of.
I then tested the Gen 2 (tvOS 15.5 latest beta) on Wi-Fi (about 340 Mbps per Speedtest on the ATV4K), and had one dropout at 26 minutes into S01E01 of Drive to Survive. I then switched back to a wired connection (about 700 Mbps per Speedtest on the ATV4K) and got lots of dropouts starting within the first minute. Odd that Wi-Fi seems a lot less susceptible to the dropouts. Can't blame it on the Ethernet hardware, though, since it does happen on Wi-Fi.
I then tried limiting the bandwidth to the ATV4K Gen 2 (still on wired) but it didn't work on my router. It kept bouncing between 0 Mbps and 50 Mbps. And yes, I did click "Apply".
Drive to Survive isn't available to stream in DV. If the program were in DV, you shouldn't lose the HDR/DV with a modest drop in bandwidth. Streaming is designed to dynamically switch between different bandwidth streams as network conditions change. Like when you start a stream, you often see it start at a lower quality, but it ramps up quickly if you have a fast internet connection.
By the way, the ATV4K doesn't upscale to DV. It does upscale to 4K. It is recommended to turn Match Frame Rate and Match Dynamic Range ON. I believe you said you have them both OFF. Turning these settings ON is like the video equivalent to sending bitstream audio to your AVR and letting the AVR do what it does best, rather than having the ATV4K decode the audio. The only downside is the TV screen will briefly turn black while it syncs to the native frame rate and dynamic range, but that is a small price to pay for better picture quality.
After almost 40 hours of WiFi ATMOS on NETFLIX I had only one audio drop for two seconds. On wired it was a bunch in just a couple hours.
When my router is limited, the bounce stays within the scope of the Mbps number I choose. Sometimes it'll bounce above by a couple. But I found, as I mentioned last night, that the ratio of being at zero or max limit is dependent on the amount of bandwidth allowed. High bandwidth, the meter will stay at zero quite a bit, and have brief instants of high bandwidth, but it never went above 130Mbps at any time.
Oh, but it is.
If NETFLIX, or any streaming service, determines that DV isn't possible it won't list a program as being available in DV.
This is what was recommended when I got the first ATV4K when it was available, so this is what I've used since.
I do, but I think it's an ATV4K issue. Somehow wired is not as good as WiFi on it. This is the first time I've used wired.
Yes, DV or not DV.
Seems we are both right. Drive to Survive is in DV starting with Season 2. The DV logo pops up on my TV when I play S02E01 and up, but not for any Season 1 episode. I have been testing with S01E01, and it was not listed as available in DV. That was actually a good thing as it helped rule out DV as a factor in the Atmos dropouts. I haven't watched the show except for testing purposes.
What you saw is the expected behavior. The average of the high bandwidth and 0 bandwidth periods will be the bandwidth of the video stream. It will do this in bursts, if possible, but limiting the max bandwidth will even this out as the max limit approaches the video stream bandwidth. I was getting maximum peaks about double what I set the max limit to, as you can see in my screen captures. I will have to investigate that. I have successfully limited bandwidth to specific devices before, but that was on my previous Asus router, which is now part of my AiMesh network.
Since I currently can't properly limit the bandwidth to the ATV4K, and we both found wired to be far more prone to dropouts than Wi-Fi, can you try my experiment by limiting B/W with the wired connection? You can start at a lower limit, such as 24 Mbps, since we both found no limit with wired had lots of dropouts. Thanks!
I have shared my thoughts on this in older posts, but you probably haven't seen those and it is worth repeating/updating.
I have been speculating that there is a subtle difference between the Gen 1 and Gen 2 hardware that the software did not take into account, affecting the MAT 2.0 creation/timing. I assume the software is essentially identical for the Gen 1 and Gen 2, my reasoning being that Apple wanted to take the easy/cheaper route of simply spinning a new board to support the A12 Bionic, and more current specs., requiring no/minimal changes to the software/tvOS. It's not as if Apple is putting any real effort into the product line.
An example of Gen 1 code that needed updating for Gen 2 would be any asynchronous code that relies on the hardware running at Gen 1 speed. On the faster Gen 2, this could result in a subtle timing error that is triggered by high bandwidth video streams or other conditions, even the difference between an Ethernet or Wi-Fi connection.
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I have my video Format setting set to 4k Dolby Vision, 60HZ. My tv gets a Dolby Vision signal even when I'm just on the menu. I can see that when I go to the tv menu. My Marantz isn't capable of displaying its menu in DV, so when I hit the menu for it, the picture goes blank and then the menu comes up. The menu isn't capable of being displayed on top. No issues there except its a pain. So on my setup, the Apple tv is always outputting a DV signal. It makes 1080p stuff look great.
I have match content turned off, and match frame rate off. I thought that was best? I do t get any timing problems between audio and video and never have to set a delay. I'd like to upscale old 1080p video to DV. It looks nice. The Amazon Firestick does the same thing.
With audio format, I have that set to Auto, Atmos Available. Don't want to disable Atmos.
Drive to Survive is available here in Dolby Vision. I'm looking at it right now. On the Netflix menu it shows Vision and Atmos both.
When I called into Apple they told me to have the Match Frame Rate turned off.
Yeah, the same thing happened on Amazon Firestick. These devices just aren't set up for a nice hardwired connection. I guess I will try pulling my wire and going wifi like everyone else.
I just tested out season 1 and it indeed is not dolby vision. I thought it was because I had match content, in video, turned off. Once I turned it on I discovered its not in DV.With match content turned off, everything comes out DV.
Ironically, within 1 minute the audio dropped out and then crackling sounds were produced. That's with match content on, so no DV, and atmos on. It was also hard wired. I've not tried wifi yet. It seems like Apple should just take the ethernet port off the device if they can't make it work right. I'm not a wifi fan, and if I knew this required running on wifi I probably would have never bought it.
So for my audio problem, having match content turned on seemed to make it worse. The tech at Apple suggested having it turned off.
Ironically, within 1 minute the audio dropped out and then crackling sounds were produced. That's with match content on, so no DV, and atmos on. It was also hard wired. I've not tried wifi yet. It seems like Apple should just take the ethernet port off the device if they can't make it work right. I'm not a wifi fan, and if I knew this required running on wifi I probably would have never bought it.
So for my audio problem, having match content turned on seemed to make it worse. The tech at Apple suggested having it turned off.
That was for a very different reason. Most older devices, such as your Firestick, only had a 10/100 Ethernet port, so Wi-Fi was often faster. That is often not the case with a 1Gb Ethernet port.
It seems like I suspected, that wifi is superior on Apple tv.
First whatever reason, using wifi is better on this I guess. Maybe the processor or something else isn't capable of processing data coming in so fast?
Frustrating to take the time and expense to wire your home for gigabit ethernet and then have this happen. Have to resort to using wifi instead.
Wi-Fi has evolved to the point that it is often better than a 1Gb wired network. Wi-Fi 6E adds more channels so Wi-Fi congestion should no longer be a problem. Wi-Fi speeds can be much higher than 1Gbps. Range issues can be addressed by adding access points or using a mesh network. When I buy the latest gen Asus routers, I use the old one to add another AiMesh node, allowing you to create a mesh network using older Asus routers.
I would not agree that Wi-Fi is superior to wired on the ATV4K. In my testing last night, I had double the bandwidth on my wired connection, and it is obviously not subject to wireless congestion or interference. You wouldn't say Wi-Fi is better on the Gen 1 that doesn't have the Atmos problem. It is just that for whatever reason, the wired connection triggers more frequent Atmos dropouts. I have no reason to believe there is an Ethernet or Wi-Fi hardware issue in the ATV4K, as aside from Atmos, video and other audio formats stream perfectly with either option.
Back to the ATV4K settings, I suggest that you do some research on the different options. Keep in mind that any modern TV should do a much better job of creating fake HDR from a SDR source than the ATV4K. You are also more likely to have lip-sync and judder issues when you don't use Frame Rate matching, as you may be adding a telecine and reverse-telecine to the video path (converting 24fps to 60fps in the ATV4K, and 60fps back to 24fps in the TV). Hope that helps.
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All I know is that if I try to watch shows in Atmos on my Apple tv using a wired ethernet connection, it drops out.Like you said, wifi isn't superior. This should not be. Wifi seems to not have the problem. So sounds like it's a firmware problem and not hardware?
Tvs don't upscale to DV, only 4k as far as I know. I've got a top of the line LG OLED 77 inch and it doesn't do it. Maybe there are some out there, don't know. LG didn't do it as of last year.
Never had a single sync issue on my settings and I've been doing it now for over 2 years since I started using the Amazon Firestick. Maybe I've lucky?
Never had a single sync issue on my settings and I've been doing it now for over 2 years since I started using the Amazon Firestick. Maybe I've lucky?
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With streaming season 1 of Drive to Survive, which is not in Dolby Vision, mine still dropped audio in the 1st minute. It was fine for about 30 seconds and then dropped. So it doesn't require a DV signal to reproduce the issue. Is season 1 even 4k? Not sure.
This shouldnt affect our problem, but I just noticed that all the menus on Apple tv are in Dolby Vision even if you have Match Content in video options turned on. So watching Better Call Saul in 4k, but not DV, the screen had to turn black before the menu comes back on as it switched into Dolby Vision mode for the menu.
