This problem has caused me to spend a lot of money and waste a lot of time. I ended up replacing my AVR with a brand new Marantz, upgraded HDMI over ethernet cabling and replaced all my local HDMI Cables. (The start of my "fun" was a black screen with audio due to the HDCP 1.4 to 2.2 incompatiblity...then I made upgrades). I have a PlayStation 4 Pro, ChromeCast HD hooked into the AVR and they both stream 4K content flalwessly. I also have the X1 hooked up to the AVR which WILL work under 2160/30. When I turn it up to 2160/60, I get the dreaded BLACK SCREEN intermittently. It is beyond frustrating. My TV is a Samsung sUHD 4K.
Bottom line, this is absolutely a flaw with the Comcast box. So, my recommendation, is to turn down the output of the box (maybe 1080p) until the thing works. My solution will be to switch to Verizon Fios when my contract is up or just cut the cord entirely. Comcast will have you replacing cables until you are broke...why they dont fix this is beyond me.
I am just a customer, playing a customer, disguised as a customer... trying to help those in the same boat.
I was informed by the original poster of this issue that it did not apply to the problem I am having. We are still not sure of the cause, but are trying a few solutions. For the post on my issue search on the topic, "My TV turns on by itself" . I have posted updates under that topic.
Thanks for your interest.
Hi Rusty. I've seen you suggest this several times. Unfortunately it doesn't work for me.
since you didn't quote the post there is no way to tell what didn't work for you. what issue are you having?
IS THIS THE HANDSHAKE ISSUE?
Just wondering I've been in this forum cause of my and other "Handshake " issues starting back before November 2018. The issue I and others started the forum for does not seem to be the same as this issue Our original issue for starting the forum has NOT yet been solved. Has it "morphed" into what you described?? Mine and others never solved BUT I did learn from others how to stop the problem
If disconnecting/reconnecting the HDMI cable makes it work again it is a handshake issue. Or possibly more quickly, switching the TV input to a different HDMI port and back.
I've been having the HDMI handshake issue since mid-2019. If I switch inputs on my Samsung TV to something else and back or unplug/plug the HDMI back in, the feed instantly returns.
Replacement of the X1 box and all HDMI cables made no difference, seems to be an inherent flaw and making me want another provider when my contact is up.
Lowering the video to 1080p did not seem to resolve the issue for me as I saw mentioned, not that I'd be satisfied with that workaround.
The problem is likely different timing between the x1 and TV as they come out of sleep/low power mode so you might try adjusting setting on one or both ends. Or checking for updated firmware for the TV.
You might actually get the best picture on most xfinity content by setting the X1 to 720p and letting the TV upscale instead of the X1, but if you watch Amazon or Netflix you'll probably want it set at 4k.