Cubase loses connection with my audio interfaces

Hi all

Recently Cubase has started to disconnect with my paired Roland studio Captures. All has worked well since going on to a MacBook Pro but recently I will be working away happily then out of the blue all sound stops and I am disconnected. I reboot cubase, not the Roland’s as the instrument sounds are still going into the interfaces, and all is well for a while.
This is a very frustrating situation.

Has anyone had this experience, solved it or has anyone any advice as to how to fix it.

Thanks in advance.

Den