Loud Beep Sound from MacBook Pro Speakers

Hi Everyone,

The issue am having is my MacBook Pro 2012 model makes a Loud continuous beep sound, the system is running ok everything works, to stop the sound all I do is close the lid, simple and opening the lid the sound is gone. but the other issue is if am editing using Final Cut and mouse over a text template the loud beep returns and when I click off it stops, and if I plug a headphone in the continuous beep blast through the headphone, pressing mute on the keyboard does not work when the loud beep starts but the laptop is fully functional, please help me, thanks