The components of a portable personal audio system include first and second audio signal source devices, such as an MP3 player (14) and telephone (16). These are connected via respective leads (12) to a control and switching stage (22), and from there to left and right audio output devices (26). User input to effect operation of the control and switching stage (22) selectively directs audio signals from one or both of the signal source devices (14, 16) to a selected one or ones of the left and right audio output devices (26).