Graid Thunderbolt 2- strange behaviour

Can anyone please help. I am using windows 10 and also Mac. My G-Raid thunderbolt 2 won’t connect via thunderbolt to either mac or PC. If I take the drives out of the bays, the machines can see the Graid attached- but when I put a drive in, the connections become intermittent and keep resetting. Basically the drives can’t be read as the connections keeps turning on and off via the thunderbolt ports.
If I plug the USB in it works fine and I can read the data.

Does anyone know what is going on please?? Thanks!