Hi @pmallett57 , Steinberg tester here. You probably could benefit from raising the AsioGuard level to high. If your instruments are not heavily working all the time, there’s a chance that this helps balancing out the load.
Another typical issue is the automatic Rec arming of selected VSTi and Midi tracks. For those tracks, a red REC button moves that track into real time mode. This means, the connected VSTis and all parts along its signal path are processed with the short latency of your hardware settings (in your case, the 128 samples). This can lead to heavy overloads. Be sure to not have a VSTi selected accidentally. The Performance Monitor can help to detect such issues.
In both cases, it’s not the lack of CPUs used by Cubase, but the dependency along the signal path, which cannot be processed by parallel threads on separate CPUs.
I hope this was helpful.
And @Magnus_N : regarding the idea that we are trying to “outsmart” the Windows scheduler: We don’t. Our code was designed when schedulers were way less smart (and dedicated to audio processing) than today. But we can’t just switch the way we do our audio processing like we would, when we were building Cubase today from scratch. Changing such fundamental code takes time and caution to not break the rest which is working fine.