Hi Folks, I'm using the HDMI 4 port on the TV to view Sky HD, Oppo 203, Amazon 4K FIRE TV, and now, an Apple 4K TV. These all switch via my Denon Atmos processor, which passes the video signal unaltered. I've encountered a strange problem, which happened occasionally with the FIRE TV but since getting the Apple TV happens every time I attempt to watch Sky channels after viewing the Apple. The picture looks most peculiar, garish colours and odd definition. To get rid of this, I have to switch the TV source away from HDMI 4 to TV and back again, then all is well. I use a Harmony Ultimate hub-type remote, so I was hoping there might be some way to overcome this problem, but I can't see any way except maybe to get the Harmony to switch briefly to "TV" and back to HDMI 4. I'm curious to know what's going on, & if there's a more elegant fix. All advice gratefully received!