Not sure if this will be helpful to all or already mentioned and buried in the thread. I was having audio sync and frame drop with 4k HDR content, and found an article using Bing AI chat (of all things) that pointed to enabling the following settings in Apple TV settings:
Settings → Video and Audio → Match Content:
Match Dynamic Range : Set to On
Match Frame Rate: Set to On
(by default, both of these were off)
Apple TV 4K (new), tvOS 17.1 (21K69)
With these enabled, my experience has been flawless all day, hope this helps others if it applies to them! Be glad to share any other details if it would be helpful. Have Plex Video Quality settings to:
Auto Adjust Quality: Off
Home Streaming: Maximum
Internet Streaming: Maximum
Play Smaller Videos at Original Quality: On
