mSata accelerator / 3 WD Black failed


Hello everybody.

I am new to the drobo 5D and i am using it for one week as a storage with my Xserve.

It has 5x WD black 4 TB + mSata 500GB Samsung.

Now i have these issues:

1: in 3 days 3 of the WD disks failed, 2 on the same slot and one on a different slot! bad luck as tech support answered me or somehting else which i don’t know.
2: my mSata is Samsung and on the dashboard now i have only 4 disks running so one slot is empty and it clearly indicates and recognize my mSata disk but it says that the hot data cache is off and accelerator is not running. Plus now is on protection mode and rebuilds the database after the failure of the 3rd disk.

Anyone can please help me on those two issues as this Drobo 5D unit is for medical data?

Thank you.