In-ear devices are currently used as headphones for listening to music, making phone calls and as assistive devices for those with partial hearing loss. Such in-ear devices fit snugly within the ear, creating a seal between the ear canal and the external environment. They also include a speaker to output audio into the wearer's ear canal. By sealing the ear canal, these devices are able to filter environmental sounds while providing the desired audio, such as music and voice, to the wearer.