No audio in one ear | Bose QuietComfort Ultra Headphones (2nd Gen)

Try a different app.

If the issue only occurs with a particular app, it is likely related to the app or app settings.

Try playing different types of media.

Different media types might produce different quality sound. For example, Podcasts, music stored locally on your phone, MP3s, streaming music services (Spotify, Pandora), videos on your device or stored in the cloud, etc. can all vary in quality. Try different media to determine if the issue is specific to certain media.

Reboot your headphones.

This reset will not erase your product settings.

If the USB charging cable or audio cable is connected to your headphones, disconnect it.
Connect a USB charging cable and charger to a power outlet. You can also connect the USB cable to a USB port on a computer that is powered on.
Note: Do not connect your headphones to the USB cable yet.
On your headphones, press and hold the Power/Bluetooth® button.
While continuing to hold the button, connect the USB cable to the left earcup. The Power light on your headphones will quickly blink twice.
Once connected, wait two seconds and then release the Power/Bluetooth button.
Tip: If your headphones don't respond after this, reset them a second time.