Follow these steps if you can't hear any sound from your headphones after playing audio from a connected source device. If these steps require model-specific information, check your manual. 1. Make sure your audio source is on and the volume is up.2. If your headphones have a volume button or knob, make sure to turn it up.3. If you have battery-powered headphones, make sure the battery have enough power.4. Check the connection of your headphones.