I recently installed Hyperion and was annoyed to discover the USB grabber I have used does not pass along CEC.
Winch means turning on my Shield TV, only powers up my Receiver but no longer the TV. Same for powering it down.
Oh, yeah it has the rainbow bars for "no signal" as well.
I'm using the KEBIDU 4K HDMI-compatible Capture Card from Aliexpress. Just so you can avoid it, if that's something you need.
So does anyone know of a grabber that has CEC pass-though, or a splitter that does?