I assume the HDMI cable that can with the PS5 Pro is a 2.1. I have the regular PS5 hooked up with a Best Buy 2.1 cable so I can use that if not.
I have an LG C1 and the three HDMI ports are slightly different, like I think port 1 is better with a 2.1 cord? So I keep the main system plugged into that port.
