Speed 4K SN850


After one week of use, I noticed that the speed for 4K Random (closer to real life use) have dramatically decreased - see pictures of Crystaldiskmark 8.0. The first test was done with 4% of the disk used and it is now 24%… so that behaviour shouldn’t be linked to the quantity of the drive saved.
I selected the option NVMe in the menu Parameters.
If you note the same problem on your drives, please let me know.
Is there a solution ?

PS : my firmware is the 611110WD