Hi Shachaf. I’ve also experienced this. But it turned out to be Windows updates in the background using all the CPU.
If it is this, best thing to do is wait untill it’s done and then restart. If you open a simple patch that you know uses little CPU, compare the average CPU to the max CPU in rack. If max CPU is jumping all over the place, it is a background process. Or else you might have to update your sound card drivers.