Apple TV No sound on startup

Hey,

we recently bought an Apple TV 4K for our downstairs TV. We have a very simple setup, sound comes out of TV that’s it. The problem we’re seeing is that when turning on the AppleTV (and subsequently the TV itself) there is no sound at all.

We’ve found that clicking the home button on the TV remove to bring up the apps then going back to the Apple TV sound then works?!?

we’ve tried absolutely every googled solution, swapping cables, HDMI ports etc but to no avail. I’ve attached a picture of our TV model if if helps.