My Samsung Galaxy A7 2017 ringtones and notifications (even in Facebook and Messenger notifications) have no sound, instead only hissing/buzzing noise is heard whenever I received a call or messages. When I watch programs in Youtube, there is only hissing/buzzing noise, there is no sound. However, I can still talk clearly when I call somebody or somebody call me (the hissing/buzzing noise is now my ringtone, hehehe). What maybe the problem? Please advice asap. Thanks.