I have a MacBook Pro (17-inch, Mid 2010 MacBookPro6,1 ) that the audio stopped working on. The audio jack has a red light on in it. In Sys Pref, under Sound, in the Output tab, only Optical digital-out port is listed. I have reset the PRAM and Reinstalled the OS. Why? Because when the mac is restarted, I can hear the start-up chime. So I know the audio does in fact work. Anyone have any suggestions before I buy a replacement logic board off eBay and replace it? I love having a 17-inch MBP and do not want to downgrade to a new 15.