C75 magenta spots on paper

Hi, we're running a large run of paper on 300gsm and suddenly getting magenta spots on the print... unwanted ones.

We've replaced cartridge, vacuumed, cleaned, emptied waste toner you name it... any clues? The spots have tiny halo around them, seem to be 'burnt' in if you follow.

 

Have you replaced the magenta drum?

 

Thanks for this... turns out was a blown fuse.

D

 

I have the same problem. but with Cyan.
Which is the blown fuse?

 

Is it the blown fuse?
108E 98520

 

In general It sounds like you've taken several troubleshooting steps already. The issue is related to the fuser unit or drum. Check for any damaged components in those areas, and ensure they are clean

 

Actually, drum and developer powder are new.
Toner drops between developer unit and drum unit.
When the dripping toner get full on top of the clear liner, it drops on the printing sheet causing random cyan spots. Have to clean manually every 20 printing sheets to clear the drops.
Replaced for testing the developer unit, fuser unit, drum unit from another good working C75. Problem remains. My units work good in other c75. Changed toner cartridges too.
Every single NVM value has been compared to the working C75.
It only says me electrical/electronic failure maybe?