Headphone jack doesnt work- software/driver issue

Hello, Im an audio guy and i had this weird thing happen to me with my friend's Macbook pro, the headphone jack stopped working after i plugged in an external firewire audio card. The internal speakers work, but when anything is plugged into the audio jack, no audio goes into headphones or any other thing fed off the mini jack. I have checked the prefs they all seem fine, and i also deleted the audiomidi and system pref user library files with no result. Well if anyone has any ideas that would be great, thanks.

1. Go to system preferences
2. Select Sound
3. Select soundflower (2 ch)

I hope that helps

headphone port

check to see if there is red light coming out of the headphone port, if it is plug the headphone jack male side into it and turn counter clockwise to remove the red light. There's a tiny switch in there that disables the audio out...