I was watching a movie on my projector with my external speakers plugged in to my Macbook and as the movie ended I pulled the speaker cable out of my headphone jack to plug it back into my Air port express.
I’ve done this before with no problem.
This time the phone jack had a red light coming out of it like the pit of hell! I couldn’t use my internal speakers, and when I went under system preferences it said: “Digital Out”
There was no choice for internal speakers.
After searching the forums I found two things can remedy this situation.
1. Plug and unplug a set of headphones a few time to get the jack to reset and the light will turn off.
2. A digital jack is a bit longer than a headphone jack, so I put VERY little pressure on the headphones be putting a small paper clip in the jack.
It seemed to be a bad idea to put a paper clip in to plugs, because I learned that is a bad idea at five years old. It turns out this is a different plug 
I did find a few forums where people claimed Apple Support told them to reinstall the OS to fix the problem. Which will definitely fix it. Kind of like tearing the house down because it needs paint.
Always ask for a second opinion, and don’t be afraid to ask for help.
thanks man, my MBP was stuck on digital out, used an optical cable (a bit longer), pugged and unplugged 4-5 times and I am back in business. If every probelm would be solved in 5 secs after taking the advice from the first webpage you stumble accross life would be sweet
Cheers,
H
my new macbook is doing the same thing. is reinstall the only help?
It is not a software problem. A reinstall will not help. I just had this issue.. I took a q-tip and cut the head off and fiddled around in the port until my volume control started to work.. It gets dirty in there and sometimes things stick..
Had the same problem with a new MBP15 (arrived today), I reinstalled Snow Leopard and it made no difference – so it’s going back to the Apple Store tomorrow! This is a stupid problem that’s been around for years – and yet Apple Support doesn’t seem to know anything about it….at least, when I phoned them I could hear them scratching their heads between ingenuous gasps and denials of knowledge of such a heinous fault.
Is there no permanent solution? Sticking QTips and paperclips, and vigorous headphone jack ‘stimulation’ seems a little low-tech to me as a fix for a known problem.
Low-tech or not, it works. Thanks for the tip! (Pun not intended but completely apt.)