Just a quick add to this, Asio guard makes no difference when Cubase will not utilise more than 14 physical cores, this is a coded limitation from god knows how long ago, so difficult to remedy, Cubase is the only DAW that has this limitation, there are plenty of threads on these very forums concerning the issue, the only way to get trouble free operation is to limit your CPU in BIOS to either disable cores or disable hyperthreading.
That is a thread when the problem started to become a problem in the mainstream, high core count CPUs were becoming commonplace in custom builds especially for real time grunt, yes clock core counts also, maybe more so, but if you can run a extremely CPU intensive VST instrument with pure clock speed grunt, you can now run 36 instances of it np, using a i9-7980X, you can in every other DAW apart from Cubase, you are limited to 28.
This is important stuff, multicore is the way the silicon is going, if software can’t use it, it’s going to crash and burn.
Here is a thread where it becomes apparent that it is a Cubase problem.
This is my last payment to Stienberg until they fix this, my next upgrade wonga goes on AATranslator, at least I can swap projects between DAW then.