While most 4K TVs are immediately compatible with the PlayStation 4 Pro, there is also a significant number of televisions that are causing problems. A specific example are some LG TVs, which don't even show a picture when you plug the PS4 Pro in, you only get sound. LG and Sony are already working on a TV update to solve the problem, but until then you can use the solution found by the ingenious gaming community.
If you have this problem, turn the PS4 Pro off. Then, keep your finger on the power button for a few seconds until you hear the second beep. This will boot the console into Safe Mode. Here, go to the HDCP settings and choose the HDCP 1.4 option. Restart the console and the image should appear normally, with 4K supported. One warning: if you decide to turn off HDCP in the options, you will not be able to watch Blu-Rays or some applications like Netflix.
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