You may have a weak battery recharge your player with the AC Adapter/charger connected to the player and the power supply * Check if your headphone plug has been inserted into the headphone jack of the unit completely� When you press the PLAY button, make sure that it is pressed and held for long enough and the mode dial is at the MP3 playback mode * Check if the volume is at an audible level. Increase the volume using the VOLUME + button * If your camcorder is in pause mode, press the PLAY button to resume playback