Apple TV 4K Random HDMI Signal Loss

Hello, same problem since the last update 16L250 / tv lg 4k 58uh635v without any concern for 1 year. sorry for my English

Hi all,

Same problem here, but only after switching HDMI cables after wall mounting my LG C7 TV. Figured the new cables didn’t support 4K HDR bandwidth, so bought a “better” one that supported high-bandwidth, latest HDMI spec, etc. Nope. Problem was actually worse.

It wasn’t until I switched back to my old HDMI cable that the problem went away. And what‘s so special about my old cable? It has integrated Ferrite cores. Huh? Could that *really* be the difference? So, I tried another new HDMI cable that I had at hand - one without Ferrite cores. Bam. Signal loss almost immediately. So I tried another cable with Ferrite cores, and low and behold, problem solved! No signal loss. Perfect 4K Dolby Vision picture.

So, all I can figure is that interference is disrupting the 4K Dolby Vision signal, and the HDMI cables with Ferrite cores prevent the signal degradation. All I know is that my old cables with Ferrite cores were and are 100% reliable and solved this problem for me.

Hope this info helps someone else!

Cheers

At first it did appear the LG update fixed the signal loss issue for me but it did not. I can say the issue seems a bit different now then it was but it still drops out. Now when I get the dreaded signal loss there appears to be some further attempts by the TV and ATV to re-establish connection but it still fails. I'm not sure if this is then really just a cable issue or more a handshake issue between the TV and ATV (which could still be a cable issue in the end).

That is frustrating. Have you ever tried the Dolby vision setting on your ATV4K?. While my cable is not the new HDMI 2.1 "Diolby Vision" cable I can watch Dolby Vision even though I do get drop outs every once and a while.

Have you shut OFF the "HDMI HD Deep Color" setting on the HDMI port your using to connect your ATV4K TO your TV? That has to be enabled for you to get Dolby Vision OR 4K HDR resolution from the ATV 4K..... but NOT for 4K SDR. So I would recommend switching off of Dolby Vision and switching off HDMI DEEP COLOR on your TV and seeing if you get the single loss while using 4K SDR. And if you dont, try re-enabling HDMI HD DEEP COLOR, and then switch back to 4K HDR 60hz and see if the issue persists. The cable being the issue is not out of the realm of possibility, but nowhere does it say that the new HDMI 2.1 cable is REQUIRED to use Dolby Vision. But it is possible I suppose.

For my setup, I am using 4K HDR 60Hz with HDMI HD Deep color enabled and have not experienced any single loss or drop outs since I switched from Dolby Vision to HDR 60hz. So I'm not convinced that this is an LG OLED issue and more of a Dolby Vision issue on the ATV4K's end. Of course I could still see some single loss or drop outs. And I will update if and when it happens. But for now.

UPDATE: The "No Signal" message has shown up again after a few good days with new Echogear cables. Most often after the ATV4K has been sleep for a while, it has trouble sending the signal to my Sony. Often I get audio, with no video. Restarting ATV4K seems the only sure remedy at the moment. Usually one restart lasts for my entire viewing session.

Looks like I will be living with this pain until Apple address the issue.

I feel your pain man, this really is seeming to be a 100% ATV4K issue. People are experiencing this same issue it across multiple brands of televisions. And Apple dent really care to fix it. I have not had this Issue with the Amazon FireTV 4K. or Any other 4K streaming device I have. Granted I dont think Amazon Fire 4K is Dolby vision ( please correct me if I'm wrong). I'm just Having the same intermittent issues with the EchoGear Cable that I was having with the "regular" HDMI cables. glad I didnt shell out for that ridiculously expensive Belkin cable.

That suggestion from Apple shows that they have NO idea whats wrong with their hardware/software. It is 100% not a "sleep" issue. The ATV4K stays ON even after the single is lost between the ATV4K and the TV, its not asleep. Apple has no clue whats wrong here. Its not the TV, I have had no issues streaming 4K content with the Amazon fire 4K. Although I dont think thats dolby vision like I am using on the ATV4K. So its hard to say.

I would give the Echo Gear HDMI 2.1 cable you can get on Amazon a try, that "improved" single loss issue, instead of getting multiple losses a day I just get them a few times a week now. But it did not solve the problem completely. Give it a try. But I wish Apple would get on the ball here.

Until recently I used the Apple TV 4k on a LG OLED B6 55" and never had any dropouts in any display mode. A few days ago I upgraded to a LG OLED B7 65", and now I get a black screen with intermittent flickering noise almost every time I turn on the Apple TV. If I restart the Apple TV there is a chance I'll get another dropout, but if I don't I'm dropout-free for the rest of the viewing session (so far). I'm going to try various cables, but this seems like a HDMI or HDCP handshake issue.

One month without black screen. The solution for me is to plug my Apple Tv 4K into a non-ARC HDMI port on my LG B7. Also, all my other devices are connected into a non-ARC HDMI port. Now I can enjoy Dolby Vision 60Hz and HDR 60Hz without picture dropouts on my Oled TV.

Problem still persists even with the right cables. I'm using the 48Gbps Belkin cable from my LG OLED65C7 (non-ARC port) to my Onkyo TX-NR676 receiver and the Echogear 48Gbps cable from the receiver the Apple TV. The problem disappeared for around 2-3 weeks after installing the new cables but it just happened twice in one night: black screen with audio and white static flashes. All I have to do is pull up the Onkyo setup menu and then exit out and the Dolby Vision resets, but this shouldn't be happening!

sparky8971 wrote: What throws me off is …

You are absolutely right. The speed rating itself won’t make the difference, as there is no HDMI 2.1 consumer equipment yet, other than the ‘ultra high speed’ 48 Gbps cables. Good ‘premium high speed’ 18 Gbps cables can handle anything that comes out of a HDMI 2.0 port. Belkin makes some fine cables, surprisingly thin and flexible, that may still improve over the cables that they replaced, but it won’t be because of the ‘ultra’ speed rating itself.

Over on AVSForum there are about 20 users of ATV4k and sony projectors who all get random blackouts on HDR titles since ‘upgrading’ to tvos12. Both Sony and Apple resort to the tired old ‘blame it on the cable’, even though all twenty of these systems (and cables!) worked great before the ‘upgrade’.

Bad titles include Ocean’s 8 (iTunes Store) and First They Killed My Fater (Netflix).

For the record my 4K Oppo BluRay player has gone Through several firmware updates without ever having trouble playing a title, through the same cable on the same projector.

Apple should open up the iTunes Store to competent third party hardware vendors.

It is a definitely a firmware issue. I tried a combination of every cable I could buy, including their overpriced "official" one with no luck. I had to sign up for the appletv beta to upgrade to a newer firmware and since have not had a single occurrence. I have since switched back to my $10 amazon basics cable.

I have an LG OLED55C7P & and the Apple TV 4K connected to HDMI 1 via the Apple Recommended Belkin 48 GBPS HDMI cable. The LG is on Software version 05.80.15. I have HDMI Ultra Deep Color turned “on” on HDMI port 1.

First off, I’m not experiencing any random HDMI signal loss. On the Apple TV, under video and Audio Settings, I’ve tried both “4K SDR” and “4K Dolby Vision” formats. Both at 60Hz. No random HDMI signal loss when viewing HDR or Dolby Vision content (ie via Netflix, Amazon Prime, Apple purchased movies, etc...).

Other settings on the Apple TV: I have Chroma Set to 4:4:4 and under Match Content, I have both “Match Dynamic Range” and “Match Frame Rate” turned on.

With both Netflix and Prime Video apps, and iTunes purchased movies, I see the HDR or Dolby Vision symbol show in the upper right hand of the TV (depending on the source content) regardless of whether the “format” on the Apple TV is set to “4K SDR” or “4K Dolby Vision”. It appears to switch correctly to match the source content format.

However, I have YouTube TV as my TV service. On the YouTube TV app on the Apple TV, if I have the format on the Apple TV set to “4K Dolby Vision” all shows I watch on YouTube TV are being up converted to Dolby Vision. If instead I have the format on the Apple TV set to “4K SDR” the YouTube App on Apple TV uses my regular 4K SDR format. This is the only app on the Apple TV (that I use) where the format switching is not working correctly (ie given my settings under “Match Content” on the ATV 4K.

If instead I use the LG Smart TV YouTube TV app....the TV detects it’s not Dolby Vision or HDR content and uses my regular 4K SDR settings (ie Bright Room Expert in my case).

To me, it appears that the problem is with the YouTube App. itself....for the ATV 4K (ie versus being a problem with the LG C7 or the Apple TV 4K).

So, if I choose to watch YouTube TV from the App on the Apple TV 4K box, I’m really forced to set the ATV 4K video format to “4K SDR” (instead of Dolby Vision 4K) in order for the YouTube TV app to use my regular 4K SDR settings (ie Bright Room Expert).

Given the above: What am I really missing by just setting the video format on the ATV 4K to “4K SDR” (ie instead of Dolby Vision 4K) and setting the “Match Content” options on the ATV 4K both to “on”? Am I only missing the “icons” (ie the display) on the Apple TV box itself from showing in Dolby Vision? If so, not a bit loss in my view. It seems all of my content is properly switching to the correct format when using the “4K SDR” format setting. Maybe Google (or Apple) can get a fix soon for the ATV 4K apps that are not switching format correctly when the ATV 4K format is set to “Dolby Vision 4K” (ie YouTube TV app for example).

Am I missing something?

I have been having ongoing problems of various kinds with my ATV4Ks and my LG 65B7A, those mentioned in this thread but also occasional audio skips, TV power turning back on by itself, and ATV complaining about a poor HDMI connection even though it keeps working. I have tried many cables of various lengths and qualities, various HDMI ports, swapped in ATV4Ks from other rooms, and prayer. I have a cause to suggest that I have not seen mentioned here: poor HDMI cable connection to the TV or ATV. I have more or less solved the problem.

My LG TV has soft metal HDMI jacks that bend easily under the pressure of a thick HDMI cable. This may degrade the electrical connection, and I suspect that the ATV4K, the LG TV, or both, or certain software, are sensitive to this. With a small flathead screwdriver, I gently bent the TV's HDMI jack shells inward, and that made a big difference. I have since turned off the TV's SIMPLINK CEC function, and that made it quit turning itself back on. I suspect that also was a cable connection issue, because the problem got worse when the TV was warm.

Manufacturers of expensive TVs should use much better quality jacks, and system/software developers should - if they can, with these high bandwidths - assume that connections will be imperfect. In the meantime, until a new HDMI standard uses locking connectors, we can buy little clamps to lock down our cables, be very gingerly with the jacks, and if necessary bend them back.