A host interface for a media device comprises a first and a second host audio terminal for receiving a first and a second analog audio signal, a first and a second connector audio terminal for connecting a first and a second pole of a four-pole connector, and a host control circuit. The host control circuit is adapted to detect whether a device requiring a supply signal over the four-pole connector is connected. If no such device is detected, the first and the second analog audio signal are passed to the first and the second connector audio terminal. If such a device is detected, the first connector audio terminal is connected to a supply terminal.