Dropouts and CPU

Hello. With CB 10 and high Sierra, I’m using an iMac Pro 2018 with 128 GB of RAM. It’s going into a waves MGB Madi interface, and finally into the Avid MTRX made by DAD. I have three instances of Vienna ensemble programs for a few instruments, and a few internal instruments that come with the DAW software. There are about 12 audio tracks. I’m running at 96 kHz/32 BF. This is all through Waves Soundgrid software. No server.
I am experiencing drop outs randomly after hours of working in the middle of a mix, and other times I get CPU overload. The CPU though is barely being touched. All the clocking is set up properly. However when I make the BURL Mothership the master clock and run the MTRX off of it, it stops. However the clocking appears to be working in any configuration from the choices. So I do not know if it’s the MGB hardware that converts network into Maddie, or if it’s a Cubase does not like soundgrid - or soundgrid in this configuration. ProTools does not experience these drop outs. Is anyone having this problem? Thanks for your help. PS. Would I be better off using a PC? One user says that CB was always made for PC and is less buggy. Perhaps even using QBase 11 which I already purchased, in conjunction with windows, would solve this. I do not know. I have a PC here but everything is on my Mac and it would be easier to stay on Mac. All the best