MISCELLANEOUS SETTING
If you connect a device that needs to use the full HDMI bandwidth, like a video game console or a PC set to output at 4k@60p 4:2:0 10 bit, 4:4:4 or 4:2:2, you'll need to connect them via the HDMI port 2 or 3 and set the 'HDMI signal format' to 'Enhanced format', via the 'External inputs' setting pages.