BRAND new iMac 5K displaying issues...

i replaced an iMac 5K fusion with an sad version. had not issues other than audio drop out with the fusion drive setup, BAD for recording, which i do.

switched to the flash drive as that has been flawless on my laptop [macbook pro]. but i am having all sorts of issues with the ssd iMac.

- lag with windows opening and resizing

- contents of windows massively scaled for a second when windows open

- graphical monitoring lag in Logic X

- issues installing software, that i just installed on a Fusion drive mac two days earlier.

- logic no retaining pathing setups for external hardware in templates. i have to reassign each time i open logic

- settings with MOTU hardware are not being retained

have their been cases of faulty flash drives on the new iMacs?