1. An electronic device having an audio function, the electronic device comprising: an exterior housing; a first acoustic radiator forming part of the exterior housing; an acoustic transducer coupled to the first acoustic radiator; and coupling means attached to an exterior surface of the first acoustic radiator, the coupling means being made from an elastomeric material, the first acoustic radiator being configured, when the electronic device is in a first mode of use, to radiate a first sound signal into free space in dependence on an electrical audio signal received by the acoustic transducer, and the coupling means being configured for acoustic coupling of the first acoustic radiator to a second acoustic radiator, when the electronic device is in a second mode of use, such that the second acoustic radiator is operative to radiate a second sound signal into free space in dependence on an electrical audio signal received by the acoustic transducer, wherein the coupling means is shaped to prevent contact of the exterior housing with the second acoustic radiator when the coupling means is located against the second acoustic radiator when in the second mode of use.