Short SSD/Nuendo freeze after stopping record

I have a problem with my brand new Samsung 850 evo SSD. I just installed it on Marvell 91xx sata 6g controller in my daw (the only Sata3 controller…the Intel one is Sata2 type).
I use it for audio streaming/Nuendo project folders. It seems running very fine during data transfers and loading projects (greatly faster than HDD) but it hangs Nuendo for a while after stopping recording. Nuendo freezes for one or more seconds (depending on length and number of tracks recorded) and after it returns in normal state.
The disk performance bar has small peaks (hitting record and arming tracks also) and very slow decreasing to 0 state after recording…
The issue is not present using my other disks (Seagate HDD and Samsung 840 SSD - used for OS).

Can you help please?
What could be the cause of this behavior???
Thanx in advance…

…any help would be greatly appreciated… :slight_smile: