I built my PC 3 weeks ago and I've had this on every driver released since then. It's driving me nuts. Even with DDU and reinstalling from a clean install it still happens.
What will happen is my fans will suddenly start going nuts, something like 80% or something and then they will simply stay there. Even when the temperatures drop back down to 30 degrees they will just keep spinning away. I then have to go into Wattman and toggle the fan control from Auto to Manual (or vice versa, as it happens in both states) and hit the Apply button. Only then will they slow down.
Can you please look into this because it's been happening for the last 3 or 4 driver updates. Getting stuck at 80% fan speed is ridiculous.