I just found these pictures in the dead pixel thread here on reddit:
Look at the third picture. That’s a BOE panel and the mura effect is clearly visible. My SD OLED with a Samsung panel looks just like this. Can you please please take a few pictures of both your units displaying the desktop or the home menu and upload them?
Manually force the GPU to 1600mhz on the home menu and use some sensitive headphones and you’ll hear it easily.