Tinnitus is the perception of sound. It is often described as ringing, buzzing, roaring, clicking, humming, or hissing. The sound can be constant or periodic. The way patients experience tinnitus is highly variable. Tinnitus can be present with or without hearing loss. Noise exposure is one common cause of tinnitus. Therefore, hearing protection can help to prevent tinnitus. Tinnitus can also be caused by ear infections, stress, excessive ear wax, high blood pressure, and other medical conditions.