A method and apparatus for improving the mute function of an IP telephone is disclosed, where the method comprises determining, by a transmitting IP telephone, whether the mute function has been activated; and if the mute function has been activated, then providing, a predetermined output. The method includes the addition of a sulfate-binding material to reduce the formation of jarosite species during pressure oxidation. The flange is capable of moving between an initial position and a final position. A first spacer is attached to a rim portion of one surface of the vibrating plate, the first spacer being interposed between the vibrating plate and one of the backboard portion of the housing and the display panel. The holder mount may be attached to the base by an articulation joint.