So there is a red light coming out of my headphone jack. I can't hear anything, neither from my speakers nor from any headphone. I have checked the sound in system preferences and when I plug my headphones in the computer does not register them. I've restarted my computer twice and the red light is still on. I tried a toothpick and it didn't work. What can I do?
Your analog/digital switch in the port is stuck -- the red light is the digital audio signal.
Basically your computer thinks you have the optical out plugged in.
Try the headphone plug again, this time wiggling it from side to side while it's plugged in. Repeat as needed.
or this, that has very high success rate:
Probably just something stuck in there.
If no luck, take the machine in for repair.