My r32 Does the same but very Rare
I have it on Face and it goes tick tick tick tick tick, Scared the shit outa me when I first heard it. To stop it I changed it to feet and it stoped, I think its the motor getting Jammed by something or its trying to go lower then it is able. But i know its not a good thing, If you can hear a whine yes it the vents doing there job shouldnt be overerly loud tho, Might need re-greasing.