With a huge 35 hours of battery life, you’ll have enough power for even long trips Away with these Whch510 headphones. If your headphones are running low on power, a 10 minute quick Charge will give you up to 90 minutes of play time. The sleek, swivel fold design not only delivers a minimalist style, but also makes them easy to fold and store, perfect for travel. There’s also a high quality built-in microphone, enabling hands free voice calls without the need to access your phone. What’s more, with the Wh CH510 headphones, press of one button and you can connect to your smartphone's voice assistant to get directions, play music, and communicate with contacts. Follow these steps if you can't hear any sound from your headphones after playing audio from a connected source device. Make sure your audio source is on and the volume is up. If your headphones have a volume button or knob, make sure to turn it up. If you have battery-powered headphones, make sure the battery have enough power. Check the connection of your headphones. Bluetooth connection: Make sure to select your headphones in the Bluetooth settings of your audio source. Make sure there are no multiple devices that emit radio waves nearby; Turn your headphones off and on. Pair your headphones to your audio device again. Try connecting your headphones to another audio source. If the sound is heard, the first audio source may require repair. If your headphones don't produce any sound after connecting to a second audio source, your headphones may require service.