No output devices found

Hello All,

I recently installed a new display assembly on the macbook and had some issues. I finally got the display working when i realized that the audio cable was in backwards pins side up instead of down (dumb mistake). When i put everything back together I was worried that the sound may not work. sure enough its not working. not internal speakers are seen by the computer. the error is no output devices found. I reset the PRAM. and even reinstalled OSX. I have checked all my internal connections to the logic board. i ran a hardware diagnostic and its not seeing any issues. I am worried that the audio board and the cable might be fried... any ideas would be awesome.

PS. plugged in headphones and no go.