Make sure your headset and the mobile are within 10 meters range
Check for the Volume level, make sure volume should not be low
Note: To increase volume on the headset make short press on the Vol+ key, Press & hold will change the music track
Sound problems may occur due to an issue with the Music player, try playing the same track with a different music player to notice a difference.
Chances are, you might have an issue with the mobile. You can check if the headset is working well using a different mobile.
If the issue still persist with an alternate device please raise a complaint on our support portal.