Adjust handsfree sound to the proper volume. Loud sound may damage you ears. For traffic safety, never use the headset while riding a bicycle or motorbike. While driving a car, it is dangerous to increase the sound volume too mush because you can not hear external sounds. Take great care about traffic around you.
+ Long press : the last song/is a platform
+ Short Press: turn up the volume
+ Switch, call can be connected when the call listen to music can cut song
+ Long press: next song/next radio station
+ Short press: lower the volume