74Responsible ListeningCaution!: Avoid potential hearing loss.Damage to hearing occurs when a person is exposed to loud sounds over time. Therisk of hearing loss increases as sound is played louder and for longer durations.Prolonged exposure to loud sounds (including music) is the most common cause ofpreventable hearing loss. Some scientific research suggests that using portableaudio devices, such as portable music players and cellular telephones, at highvolume settings for long durations may lead to permanent noise-induced hearingloss. This includes the use of headphones (including headsets, earbuds, andBluetooth or other wireless devices). Exposure to very loud sound has also beenassociated in some studies with tinnitus (a ringing in the ear), hypersensitivity tosound and distorted hearing.Individual susceptibility to noise-induced hearing loss and potential hearing problemvaries. Additionally, the amount of sound produced by a portable audio device variesdepending on the nature of the sound, the device settings, and the headphones thatare used. As a result, there is no single volume setting that is appropriate foreveryone or for every combination of sound, settings and equipment.You should follow some commonsense recommendations when using any portableaudio device:• Always turn the volume down before plugging the earphones into an audio source.• Set the volume in a quiet environment and select the lowest volume at which you can hearadequately.• When using headphones, turn the volume down if you cannot hear the people speakingnear you or if the person sitting next to you can hear what you are listening to.