Hi, last day my macbook air usb port don't work well... I don't know how but if I plug a mouse, pendrive, usb hd the light on the devices is on... I think it's must be ok... BUT I can't use... no mouse no pendrive no superdrive nothing on my desk I don't see nothing. So I called the apple center near my city and he said that I can try the PRAM reset... well... but the situation not change... how appened? my air is never fall down... thanks for answers.