Apple TV 4K Random HDMI Signal Loss

Sorry - again, I would first make sure the OS is up to date and then get that Belkin cable and try using the non ARC HDMI port but make sure you use the correct HDMI port on your TV that is 4k functional (its usually HDMI 2 and 3).

What exact TV are you using - ie model #.

Bought the Belkin Ultra HD High Speed HDMI Cable, and changed the setting to Chroma 4:2:2, because the regular HDMI cable on 4:2:0 was not working. I haven't had any problems and the picture looks sharper.

I can confirm that using the Echogear HDMI cable fixed the issue for me too. Bought the cable 2 weeks ago and no problems.

I went back to my Costco HDMI 2.0 cables while keeping Match Frame Rate turned off and it still works perfectly so that was the problem for me apparently.

I had dropouts even though I have a Dolby vision capable tv

Switching to the Belkin solved my problem

Reset my Apple TV 4K out of frustration and have it hooked up to the HDMI arc port. So far, so good.

No, connect your AppleTV directly to your TV (non-ARC port). Then connect your sound bar to the ARC port. Then adjust your audio settings in your TV to allow the sound to go through the ARC port (sound port). Your setup should look something like this:

Apple TV —-> HDMI 1 (nonARC)

Sound bar—-> HDMI 2? (ARC port)

I just got my 3' Monoprice Premium cable and it works a lot better than the generic one I was using before. I'm using a non-arc port.

But, it's not truly fixed. I turned on HDR 4K 60hz and it's still flickering. I had to change it to 4k SDR 50hz for the flickering/signal loss to stop. Just like everyone suggest this just seems like a work around and not a fix.

I also switched it from 4-2-0 to 4-2-2 and it was just a blank screen that looked like it had no signal.

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

Michael, I have exactly the same setup that you do: The Onkyo receiver, Apple 4K, the LG OLED65C7, and even one Echogear cable and one Belkin cable. The only difference is that my Belkin cable runs from the Apple TV 4K to the receiver, and the Echogear from the receiver to the TV. So far, no problems.

My guess is that if you replace the Echogear with another Belkin cable, the problem will go away.

mick0016 wrote:

The only sure solution for me was to kick it down to Dolby vision 30hz (which has obvious drawbacks)

With most video content being 24 Hz (24 fps) and a few 30 Hz (30 fps), that is not really a drawback.

I have the same problem and have seen it at least with 10 other friends. It’s from 4K projectors to 1080P TVs. No matter what cable and no matter what specs, this occurs and I can almost time it on a few systems.

For me I’m using an Epson 1080P projector, high end custom installation cabling (I’ve been in the industry for 10 years), and with zero issues on other devices. The only device that has this problem is Apple TV and it’s not just the 4K version.

It normally happens within the first 5 minutes of any show.

The key here is it’s related to some sort of syncing issue when moving from app to app or from show to show. It has to be around this.

Unless, Apple has deflated certain specs and actually isn’t fully compatible with industry standard cabling, and may be ahead on some things. I don’t believe this to be the case, but it could be. They were last with 4K and still don’t support year old surround sound formats.

I think it happens on more demanding apps, videos (higher resolution) and higher fidelity audio. Even though Apple TV hardly supports any current audio decoding.

It’s like when a movie moves from the intro to the actual movie. This is where movies move from even wider formats for theaters to 16:9. This is definitely a trigger of some sort and requires a sync.

I see this flickering at least 5 times and day and it’s normally within the first 5 mins of watching. At times it can happen during the middle, but it always seems like it’s a peak part of the movie.

Not sure but maybe this steers the Apple folks the right direction.

This issue has caused an insane amount of disruption in the custom installation and smart home industry, because Apple doesn’t take any responsibility.

This is an Apple problem, not a cabling or TV issue. I’ve seen it too much and in too many different scenarios. The only common denominator is Apple TV.

This is not an LG issue. Maybe recent posts have focused on LG, but this is a lo-o-o-ong thread and includes other brands. My equipment is Sony and Marantz. I got some relief by upgrading to 4K cables, but only surefire fix for me so far is to reboot ATV at the beginning of each viewing session (I've programmed my Logitech remote sequence to do this).

Hello, I wish I was as lucky as you!

Using the Belkin Ultra High-Speed 4K HDMI Cable (2m) on Apple TV 4K running tvOS 12 with LG OLED 55C8 has not solved the issue for me.

I have a case number with AppleCare too and am awaiting a response from Engineering.

Both workarounds work:

- Turning off Dolby Vision and using HDR10

- Using 4K Dolby Vision at 30Hz

But these totally defeat the purpose of owning these products.

It might be a software problem ,or maybe not. It had only been doing it for a short time on my system. Then yesterday I pulled out a different HDMI cable, that is different from my generic cables. It has GE stamped on the finger grabs.

Been working perfectly ever since.