Problems with XMP on Asrock z390 Phantom 6

So I recently bought a pair of 16gb RAM sticks of Kingston Hyperx, which run at 3200 from stock XMP certified. My PSU is a Gigabyte 750.

They are both installed in A2 and B2.

I enabled the XMP and for 1 day everything was going fine, literally 24hs with the computer active. (mostly google chrome, visual studio and some other stuff, not too heavy).

Fast forward 1 day later, I have my stuff opened and I launch a game. Computer completely freezes like a statue when I go inside the game past the menu. Restart, re launch the game, froze on main menu after like 5' of stand by. 3rd time froze even before going full window, on the loading screen. (between each try I tried putting the voltage up a bit, from 1.35 to not more than 1.38. It did seem to provide more stability, but it ended up freezing nonetheless.

Then, I manually put down the ram from 3200 to 3066 mhz, left the computer on with a lot of stuff opened including the game and went to sleep. Woke up, and everything was working perfectly.

So I started googling and read that Asrock is known to have XMP issues with 3200 ram?
I read about having to turn down VCCSA and VCCIO values.. But i would like some better assistance on what to do.