RGB doesnt work YCbCr works

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I'm using a Samsung S24E390 1920x1080 LED PLS monitor and the issue I'm having is that in the AMD control panel when I adjust the pixel format to RGB 4:4:4 (RGB Full) the colour is absolutely amazing but the blacks are much too dark to the point where it's really hard to see blacks or shadows in any type of media.

The workaround however is for me to use YCbCR in 4:4:4 pixel format which balances out the blacks but leaves the colours looking a bit dull especially in comparison to the RGB setting. I've tried tinkering with the monitor's OSD but the monitor's OSD doesn't work with HDMI input being used so OSD is disabled in HDMI mode. The monitor itself has colour profiles available on the support page on their site but it makes absolutely no difference I even tried using their own driver which just changes the name of the display in the device manager from "generic display" to the original monitor's model.

Does anyone know a fix to this or is my monitor faulty?

[UPDATE]
I did some more thinkering and found that if I overclock the monitor's refresh rate from 60Hz to 70Hz and set the timing standard to CVT from the manual setting (I've tried all available timing standards) the RGB setting works when GPU scale is turned off but it looks exactly like the YCbCR setting so I assume that it isn't even switching over to RGB colour just reporting that back to me in the control panel. When I enable GPU scaling again it makes the RGB colour setting look dark again.

Also to add another note I've actually bought 3 branded high quality HDMI cables and the exact same issue is replicated across all of them so it's definitely not related to faulty cabling.

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I managed to correct this issue by setting HDMI Black Level in the monitor OSD from "Low" to "Normal". Works fine in Full RGB mode now.