This is an industry wide issue. Mostly reported on Sony Tv's but always with Apple TV 4K. Posts on Mac forums, reddit, everywhere. In this instance, it's not your cables, is simply an issue with Apple TV. Of course the job I've been troubleshooting it for months is a cord cutter and his only source of TV. I've eliminated the matrix switch and went loan to each Apple TV and the problem still exists. This has made me look like a fool on this job and there is nothing I can do about it. A reboot will fix until a period of inactivity then it happens again. Im done with Apple.