CPU usage very high when doing nothing!

Hoping someone can help!

Fresh install of Cubase 9.5 on an i7 8 core 4GHz CPU with 16GB Ram and all round high spec PC.

No other apps except for a few choice VSTs on completely up to date Windows 10.

Even with 2 or 3 tracks playing and what I consider to be a minimal load, the CPU meter goes mental and audio drops out. This seems random - not consistent by any means. I’m using a Focusrite 2i4 with latest drivers.

The CPU monitor in Task Manager / Resource Monitor shows low usage all the time.

Where to start? Is this a Cubase problem? Seems like it’s just not playing nicely with the hardware or not managing resources efficiently.

Anyone else had this problem, what did you do?

Many thanks in advance for any pointers!