A device and method to protect a user’s ear from changes in external atmospheric pressure and to treat middle ear disease by actively controlling air pressure in the user’s outer ear cavity. Both the photoelastic birefringence and the intrinsic birefringence are expressed in a tensor format simplified by the symmetries of cubic crystalline structures. 5 cps at very low temperatures of about 30\xb0 C. The salt value and the salt identifier may then be provided in response to the salt value setup request to enable the salt identifier to be stored in association with a first hash value generated from the salt value and a customer password for future customer authentications. The configuration settings are sent to at least one computing device that is adapted to modify the media based on the configuration settings to generate modified media.