We have tried both wifi and ethernet connections, have changed all the HDMI cords.
TV is a Samsung Q8DT and we also use an apple tv 4k as well as PS5. We mostly use the apple tv, but have experienced the issue with apple tv and native samsung apps.
I think its been happening ever since I got the Arc, I love the Atmos but this happens every time we watch Atmos content and really kills the movie.