A:Answer I had this same problem too, especially while using a connected 4K Apple TV. I’ve done all the troubleshooting (factory reset, testing with different HDMI cables and devices).
Hisense tech support sent me a useless firmware update (version I0207) which is older than the current version (I12030) available from automatic updates.
Since the product is out of warranty, I was advised my only recourse was to take the TV to local repair shop.
Never buying Sharp/Hisense again!
