I am attempting to connect an older non ARC Integra AV receiver to a TCL 6 series and an Xfinity x1box. When I add the receiver to the HDMI port and attempt to turn the system on, the tv does not recognize the xfinity box. I receive a message that there is not cable box power. So no audio or video. I am assuming it is not recognizing the cable box is running through the Integra receiver (DTR 5.8). Do I need to somehow let the tv know the cable box is connected to the receiver? I inherited the system when I bought the house and am not that familiar with every connection. System worked fine with an older Samsung plasma.
All you should have to do is be sure you have selected the correct inputs on both the receiver and the the TV, assuming the xfinity box is configured to send a resolution your receiver can handle (probably not 4k, but if you had that working with a different TV it should continue to work.
Alternatively you could try connecting the xfinity box to one of the TV HDMI inputs and use the optical output to send audio to your receiver. If you have the xfinity xg1v4 this would let you use 4k to the TV although you might need a new HDMI cable and there is really not much 4k content on xfinity.
Another alternative is to use the roku xfinity app/channel on the TV instead of needing the xfinity box at all although then you need the optical connection to the receiver to get audio at all. And if that is your primary/dvr box if you return it you would only have cloud recordings.