After some updates i noticed my sound not working. it has the symbol of mute but the mute button is not selected in the menu the out put says no devise selected what can i do to get my sound to work again.
Seems to be hardware but try:
PRAM RESET. http://support.apple.com/kb/HT1379
and still not working
re update the machine. Download this and re update 10.7.4( if you are 10.7.4) http://support.apple.com/kb/DL1524
Apologies this is the 10.7.5 combo update (if you are already 10.7.5) The one above is 10.7.4
Retrieving data ...