Newer Mercedes Benz cars will play pink noise at 80db through the car stereo if the sensors detect an imminent collision.
"When presented with a high-intensity sound stimulus, the
stapedius and
tensor tympani muscles of the
ossicles contract.
[1] The stapedius stiffens the ossicular chain by pulling the
stapes (stirrup) of the middle ear away from the oval window of the
cochlea and the tensor tympani muscle stiffens the ossicular chain by loading the
tympanic membrane when it pulls the
malleus (hammer) in toward the middle ear.
The reflex decreases the transmission of vibrational energy to the cochlea, where it is converted into electrical impulses to be processed by the
brain." -Wiki