Poor video quality/posterization on Apple TV Channels app


I have an Apple TV running through a Pioneer Elite SC-LX801 to a Samsung UN49KS8000 Quantum Dot LED UHD TV. The image quality of the Channels app is very poor, with extreme posterization in dark parts of the video. I tried using the HD Homerun app on an Xbox One X, and the video is way better (looks the way you'd expect). Anyone else run into this and have any suggestions on what I can do to fix this?


What hdhomerun model and channels?

How does it look on the ATV using the InstaTV or VLC apps?


Another thing to check is whether the ATV4K is set to SDR mode or HDR mode.


HD Homerun model is HDHR3-CC (HD Homerun Prime 6 unit with a cable card). Firmware is up-to-date.
Channels app is latest.

I actually hadn't known about those other apps' compatibility w/HDHR. I just tried them both, and found the same poor video quality.


I had it set in HDR mode. I also have AppleTV set to match frame rate and range. However, if I set AppleTV to SDR mode, then the video looks fine. Is this a known bug in AppleTV--obviously, the cable HD channels aren't in HDR, so why is it trying to display them in HDR?


There is a setting in the Channels app that will force the app to switch your TV to SDR mode. You can tell it when you want to do it, since it can take a few seconds and will black out the screen (either do it when the app launches, or every time you play video only).


You’ll get the best results out of your Apple TV by keeping it in 4k SDR mode as the default, and letting Match Content do it’s job when you play videos.


We were watching the Oscars live last night and the picture quality was the worst I've ever seen on the Channels app. Even people who know nothing about picture quality were asking what the problem was. Any dark shadows showed massive pixilation.

TV is set to SDR mode. Tuner is new HDHomeRun Quatro


Basically same issue here. The picture is generally not very clear and at times is pixelated. I’ve messed with the picture settings over and over which helped a little. However when compared to other apps the clarity isn’t even close. I’m wondering if it’s associated with poor deinterlacing?


I’ve been having similar issues, mostly in the dark areas of the screen. AppleTV 4K was set to HDR (not aure when) so I changed it to SDR and we’ll see what happens. For the Channels App, is there a setting for Match Content? I see the SDR switching setting, which is set to Off right now.


For the Channels App, is there a setting for Match Content? I see the SDR switching setting, which is set to Off right now.

It's a tvOS system-level setting. You can find it in the Settings app. More information here: https://support.apple.com/en-us/HT208288


Got it! I was assuming it was a Channels App setting and not finding it :roll_eyes:


I tried updating those settings as well with no change. The issue doesn't seem to be there live, but only with the DVR recordings.