kernel_task making my computer run extremely slowly even though CPU temp is v. low

Hi all,

Got a new Mac Mini M1, not even a month old, I'm having lots of problems with it running extremely slowly to the point that it's utterly unusable, and at some points completely stopped responding, that I had to pull the power plug and plug in again.

The culprit, that I could see, is kernel_task, and reading online, it seems that it only runs when the CPU is overheating, but my M1 is cold to the touch, the fan exhaust is cool, doesn't even feel warm at all. iStat shows CPU temp to be about 30-33 degrees C. Rebooting will fix this until about 30-60 minutes later, then kernel_task kicks in and slows my computer down. The only thing I'm literally doing is email, internet browsing and backing up, and absolutely nothing else - nothing that would consume the CPU. The computer is completely uncovered, no vents blocked, my office isn't warm, it's -1 degrees C outside.

See the screenshot of iStat - you can see kernel_task is using up over 40% CPU, and the CPU temp (very top right) is only 32 degrees C.

I don't understand why it's running incredibly slowly and kernel_task is throttling the computer down when it's not even warm?

I desperately need this fixed as it's really impacting on my work and my own business.

Any advice would be greatly appreciated, thank you.