An electronic device may comprise audio processing circuitry, pace tracking circuitry, and positioning circuitry. The pace tracking circuitry may be operable to selects songs to be processed for playback, and/or control time stretching applied to such songs, by the audio processing circuitry based on position data generated by the positioning circuitry. The position data may indicate the pace of a runner during a preceding, determined time interval. The pace tracking circuitry may be operable to control the song selection and/or time stretching based on a runner profile data stored in memory of the music device. The profile data may comprise runner's distance-per-stride data. The electronic device may comprise one or more sensors operable to function as a pedometer. The pace tracking circuitry may be operable to update the distance-per-stride data based on the position data and based on data output by the one or more sensors.