I have a MBP 13" running os x lion 10.7.4. The headset jack does not function at all. I can hear crackling in the headphones but not acual sound. I have attempted the the PRAM reset but I guess my timing is off because I keep running into the boot menu. I have a pair of Dre. Pro's that I am using and work fine on everything else I own. Thanks for the help
