Thanks for the note here. In Settings>TV inputs>HDMI[1/2/3]>HDMI mode, have you tried changing this to HDMI 2.0 for the HDMI port that your PS4 is connected to? Does this resolve the issue you are seeing?
Thanks for clarifying. Do you observe this behavior when first turning the TV on, or when attempting to switch to that HDMI input on the TV while the TV is already on?