My TV is a 65 inch Hisense Model 65H7608, i have no audio connected, just connected directly to the HDMI ARC 60 port, the channels work only if i reboot my set box inside the PVR trouble shooting settings.
I took a quick look and it appears that only 2 of 4 of the HDMI inputs on that TV are HDCP 2.2 compliant. I'm not sure which 2, so you may need to check the user manual or reach out to the manufacturer. Failing that, there's always trial and error!
Try the other ports, see what happens and let us know!
Can you confirm if the HDMI cords you are using are HDMI 2.2 rated cords? We would also like to confirm that 4K Box is set up to output a 4K resolution. Please go to the Settings on the remote, then Appearance, then TV Type and ensure it is set to the highest resolution. Once this is confirmed please test out those channels again to see if the same issue is persistent.
The HDMI cable came with the 4k Box so it must be HDCP 2.2, and I am actually using a gold plated HDMI cable from 2013 i believe. Although i get this error or inconvenience state from the service i am able to reboot my set box and get the channels back. Once the TV or box goes off I`ll have to repeat it but i do not turn my TV off till 1 am from turning it on at 9am. Ill just deal with it for now, its not really getting under my skin as i was able to resolve my situation my self. Thanks for you`re time. take care...