If you look at other paper stocks under an eye glass you should be able to see the yellow dots.
All machines have it and its unique to your machine.
What paper weights are you guys running? over spec weights will cut into the rollers.
If the stainless steel roller is covered in black spots you...
Sounds to me like your environment is way to hot?
Temp range is 20-27 deg and 30-70% humidity. If you keep it within this range...