So first of all I want to say that this is the second time I am having this issue.
The first time I format my Windows SO and the speeds returned to normal :
After one week where the disk was about 30% the problems returned :
(I removed a lot of data and the disk is only 11% FULL so this is definitely not acceptable at all. )
After removing data the speeds changed from 200 to 400.
I am on the last firmware. And I already tried a lot of fixs that were posted here for the similar issues with the Mp-600 .
Do someone has some ideia how to fix this ?