Pretty sure they just have uneven pad transfer as samr350 said. Do they look like there is uneven deposits? Blotchy, inconsistent color?
I’ve used this on various rotors and it works. You’ll have to remove the rotors. It’s worth the try, if it is uneven transfer layer then this will get you back down to a fresh rotor surface. But you’ll have to solve the overheating that is causing the poor transfer.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1