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Voice Disorders. A voice disorder is when the voice has a problem with pitch, volume, tone, and other qualities. These problems occur when the vocal cords don't vibrate normally. Your voice is the sound that air makes when it is forced out of your lungs and passes over your vocal cords.
Common Causes of Voice Disorders. In order to produce a normal voice you need to be able to move your vocal cords back and forth. It is the vibration of the vocal cords touching each other that creates sound. Anything that keeps the cords from moving normally, or distorts their smooth surface, changes the quality of that sound.