Hi,
to my issue, I set my DDR5 memory 2x32GB(G.SKILL F5-6000J3040G32G) to Expo 1.
Normally it should run at 1.4v VDD=VDDQ=VDDIO.
I just read about optimization online, so I tried to lower VDD=VDDQ to 1.35v and VDDIO to 1.25v which for me runs perfectly stable after several days of use...