A earpiece (10) for a sound delivery system has a sound output port (24) for delivering sound into the ear canal of the user. A cerumen block (30) is provided to prevent cerumen or earwax from blocking the sound output port (24) of the earpiece (10). The cerumen block (30) is formed by a small flap (30) of material which covers the sound output port (24) and blocks cerumen from entering the sound output port (24) in a closed position while allowing sound to pass around the flap (30) and enter the ear canal in an open position. A resilient hinge (32) returns the cerumen flap (30) to the open position once the earpiece (10) has been placed within the ear canal.