Apple TV 4K Random HDMI Signal Loss

I’m having the same issue as well. I have an LG 65” SJ8500 with Dolby Vision connected to the Apple TV 4K. I’ve tried turning the SIMPLINK (HDMI-CEC) settings off and on on both the Apple TV and LG and still have the same issue. Glad to find other people having this issue because I almost returned my TV thinking it was defective.

I don't think it's the cable length was the issue because before I purchased the Echogear HDMI 2.1 (as mentioned in an earlier post), I tried using two different 6ft Amazon basics HDMI 2.0b cables and still had the problems. I have an LG 55" 7700 60hz 4k TV with Dolby Vision (DV) running an Apple TV 4k with no problems using a 6ft Amazon basics cable. My 65" 120hz 8500 4k with DV didn't work until I bought the Echogear HDMI 2.1. I still believe the problem was the 2.0 cables can't handle the bandwidth of DV, color bit depth, and 120hz; the specs say it can't so it makes sense.

Great find! I am actually using the Apple recommended Belkin Cable for the Apple TV found here and I am experiencing HDMI signal loss with this cable:

Belkin Ultra High Speed 4K HDMI Cable (2m) - Apple

It appears the Echo Gear cable is currently out of stock on Amazon but I'm encouraged that this is the fix. Would be interested to hear if anyone else has found another cable that might be in stock that works?

After replacing my ATV4K twice, I found this thread. Based on what I read, I just replaced my Audioquest Cinnamon HDMI cable (HDMI 2.0) with the Echogear HDMI 2.1 cables recommended above. So far, no signal loss. Seems to be much better.

I also noticed other small improvements like the ability in Netflix to see video thumbnails when "scrubbing" (using FF/REW). With previous cable, the thumbnail image box was empty. I suspect there just wasn't enough bandwidth to get all the image information through quickly.

My setup:

• ATV4K connected directly to HDMI 1 on a 55" Sony A1E (using Echogear for this connection).
• My video settings on ATV4K are 4K HDR 60Hz/Chroma 4:2:2/Match Content Range & Frame Rate.

Even with the Echogear cable, I still experience a brief black screen when switching between streaming and the title screen (episode list) for a Netflix show. The cable upgrade solved the issue-- mostly. I think Apple still has some work to do here.

I'm a little frustrated that BestBuy/Magnolia folks (got TV there) were confident that the pricey Audioquest cables supported the latest HDMI standards. Should have done my homework sooner, as I would have learned that they are not HDMI 2.1. Hoping I can return them.

WORKAROUND for PROGRAMMABLE REMOTES: I added a command to reboot ATV4K in my Logitech remote startup sequence for ATV. I always need to reboot it at the beginning of a viewing session in order to clear the "No signal" problem, so why not automate it?

My Logitech Harmony Remote Startup Sequence for

Activity "Watch Apple TV":

1. Sony TV (Power On)
2. Marantz AV Receiver (Power On)
3. Apple TV (Power On)
4. Sony TV (Input HDMI 2)
5. Marantz AV Receiver (Input TV)
6. Apple TV (Reboot)

The reboot seems to preempt getting into the state that causes the "No Signal" condition. This works for me every time and doesn't add much extra time to startup.

BTW, I am using the Echogear cables, which did help, but did not solve the issue. For those of you with programmable remotes, this is a nice workaround until the problem is truly solved by Apple.

I want to provide an update on this. I believe I solved the issue with loss of audio over HDMI. The issue for me is out of sync HDMI handshake between my Samsung UN40KU7000 TV and Apple TV 4K. If you turn the TV by powering up the Apple TV, you may or may not get the proper handshake. Hence, you may lose audio. The work around is as follows:

1. Put Apple TV into sleep mode (this may or may not turn off your TV)
2. Turn off the TV
3. Turn on the TV. Do this with the TV remote.
4. Finally, turn on the Apple TV. You should now have sound.

What you are doing here is forcing the sequence of HDMI handshake signals. I still believe the culprit is Apple TV 4K, since no other piece of my gear (including older Apple TV) exhibits the same symptoms.

FYI, all HDMI cables within the given specification version are the same. Copper is copper. You are just paying for the quality of construction. I am using the following cables from Amazon:

Aurum Ultra Series - High Speed HDMI Cable with Ethernet - 2 Pack 1.5 FT - Supports 3D & Audio Return Channel - Full HD [Latest Version] - 1.5 Feet

Hi all just sharing my experience and solution as this was driving me mad and this discussion helped me find a solution.

Setup: Apple TV 4K and LG OLED B7 TV with an SJ8 sound bar attached.

Using: Netflix, Prime and Disney Life and BoxTV app (Ireland only)

Was using amazon basic and other cables including the apple branded HDMI cable from the apple store with major issues including sparkling and drop outs forcing TV and ATV restarts would happen almost once every show or film also sound sync was off and not correctable properly.

Corrected by

• buying two Philips 4K cables form Argos as per http://www.argos.co.uk/product/5537750
• One cable run from ATV to SJ8(receiver) and one form SJ8 to non ARC HDMI on TV
• Disabled content match on ATV

Tested first for a week in Dolby vision 30HZ OK

Then 50HZ for a week all ok

finally 60HZ for a week all ok.

HDR also enabled on the HDMI port automatically.

Happy to say its all finally fixed without any new firmware for ATV or LG TV.

Seems to work on all Dolby vision settings also standard, cinema etc.

Also ATV now handshakes with TV immediately, doesn't flash in and out as Dolby vision/HDR is enabled by the TV and shows remain where left off on each App which wasn't happening before so makes me think its a handshake issue on other cables and the ATV forces the TV to retest/setup/enable the settings each time which causes issues and initial screen changing/dropout later.

I never had this problem until the lastest TVos update (September 2018) - now it has blackouts every so often!

I believe it can only mean one thing:

1. it's software related
2. It's most likely cost by ATV-software
3. it could be a combination of factors - so the TV, ATV, cable and video/audio-content could all be partners in crime...

Same issue. Periodic signal loss indicated on the LG C7. To get picture back I have to turn TV off and on and then I get the Apple TV picture back. I have tried resetting the Apple TV from scratch twice now. Hope the second time works.

Same issue. I have a LG 65SJ8500 65-Inch 4K TV. The signal from my ATV 4K to the TV drops out randomly several times each day. To get the picture back, I have to put the ATV to sleep and then turn it back on. I tried all new cables. I tried factory reset. I have wired ethernet connection. Apple TV 4K signal loss is very frustrating.

Thanks Jason for your awesome comentson TV4k- I am afraid that I would go through the same problem.

So I can see here that I need to upgrade to 4kitune? I had tried whole morning to buy the TV4k but my hard

luck. I could not get customer service help for the feedback on phone..they seemed very busy. Your coments

have answered my question.

Thank you so much.

Follow up - I took my unit in and got it replaced. However I am now starting to see the same problems again. I did replace the cable and had it running to the TV with a 6' HDMI cable and had no issues. I have now reinstalled everything and am using a 15' cable - same brand. I'm not sure if the units are ultra sensitive to cable lengths?

Same issue here. Mine is an older LG 1080p TV. Sitting there watching something and then the picture judders briefly, then TV goes to ‘No Signal’. For me, the picture comes back after a few seconds, but I have to rewind the content. Very annoying. LG seems to be the common theme here (as well as th ATV4K of course).

I am experiencing the same issue with the Apple TV 4K and my LG B7 TV. I randomly lose signal when an episode ends. This does not appear to be app specific as I have lost signal in YouTube, Foxnow. I have not lost signal during playback on when an episode ends. . I have been able to restart my Apple TV by holding the menu and sleep button on the remote to get the HDMI signal back. Is this possibly an HDCP handshake issue?