Anyone have any HDMI sync problems? Have a 65” XH90 connected to a BT UHD box. All was fine.

However the last week sound (only use TV speakers) now crackles/distorts, and goes out of sync.

Switching inputs, switching TV off/on, gets it back in sync. This happens for recorded programs and live TV via the BT box.

However using the TV apps, Prime, Netflix etc everything is ok.

So tried a new HDMI lead, and different HDMI port and the same result.

So I presumed it was the BT box, however just received a new BT box and it’s the same....

So is the TV broke? Why are apps ok, only the HDMI sockets broke?

Anyone anymore help please
Thanks