Abstract: A method may include receiving, at a device, a signal from a first audio source. Audio content may be output based on the received signal. It may be determined whether a signal strength of the received signal has dropped below a threshold. Audio content may be automatically output from a second audio source when the signal strength of the received signal has dropped below the threshold.

Abstract: A mobile communication device including a connector, a judging circuit, a first transmission circuit, a second transmission circuit, a data processing module and an audio processing module is provided. The first end of the connector is for receiving and transmitting a data signal of the data processing module or an audio signal of the data processing module. The second end of the connector is for receiving and transmitting the data signal of the data processing module or the audio signal of the data processing module. The judging circuit is coupled to the first end of a connector and outputs a first indicative signal to determine the type of the plug connected to the connector.