Why I hear sound from upper front speaker or receiving speaker .

[Alee Aoun]

Hi, It's happened when I play sound via whatsapp , and screen become in-black and hang up, after that I can't even use power key to switch my mobile off . There are no issues with sensor or mobile at all . Its "Only" whatsapp matter. I need your support please . Tnx

 

[Rukbat]

It sounds as if it is a phone issue. If holding the power button in for 15-30 seconds doesn't cause the phone to restart, bring it into a repair shop and see if it pays to repair it.