Steinberg Audio Power Scheme doesn't work on laptop

I’ve always used the Steinberg Audio Power Scheme on my desktop machine to make sure my processor runs at full speed. And it does.

I’ve recently started looking at it for my laptop and it seems to have no effect. Even with it on I get pretty big fluctuations in processor speed. I’ve confirmed that it’s active in Windows 11 power settings - it says min/max processor state are both 100% while the speed is fluctuating. So, basically, it’s being ignored.

It’s not a thermal throttling issue - using HWInfo I see no indication of thermal throttling. Core temps are 65 - 70 deg C.

So, if it’s not thermal throttling, what else would cause it to ignore the “min processor state” setting on my laptop?