Make sure that your headphones are properly paired and connected with your Bluetooth enabled smartphone or music player. Refer to the “Pairing” instructions in this manual and in the manual supplied with your phone or music player if necessary.
The rechargeable battery in your headphones may be exhausted and need to be recharged. Refer to the “Charging Your Headphones” instructions in this manual.
Make sure there is no 3.5mm auxiliary cable connected to the headphones aux jack.