ok when i got home i opened my macbook then the sound wasn't working,i asked my mom if she did anything to my macbook! cause she borrows my laptop sometimes. she said she didn't touch anything naman. so i tried to adjust the volume using the controls in the keyboard then this came out! so i tried restarting my macbook! i heard the start up sound. but i still couldn't hear music or anything else from my macbook! can anyone help?