A hearing aid (8) comprises an inlet port (6), a sound tube (12) for conveying sound to the ear piece (13). The invention further provides a component for a hearing aid comprising a slab (26) having an exterior surface, which is super-hydrophobic. The component may be any one of a housing, a casing, a shell, a faceplate, a grid, a hook, a lid, a battery drawer, a button, or a manipulator. The invention also provides a method of manufacturing a component for a hearing aid.