[repairman54]

You might be hearing the active shutters opening since you only hear it when the AC is on when slowing down.
No issues with my '20 High Country, 15k miles, since turning off the auto. braking features.

 

[repairman54]

They meant Adaptive cruise control (ACC)

Thanks, I thought it was just a typo. I've got that crap turned off in my HC along with the auto braking that braked for the invisible man. Once and done.