Sound locked

I'm having the exact same problem. Strange thing is the sound still works perfectly with my headphones in; however, when i try and play any sort of sound with no headphones in, the music stops and when i try and change the volume a prohibited sign pops up beneath the volume level.

When the headphones are not in in, the selected output device in system pref. is name: digital output, type: built in output.

This is really an annoying problem, help would be much appreciated.

I am having the same problem. When I put my headphones in, everything works fine. But the moment I take them out, a red light comes on in the headphone hole, and the sounds will not turn on. My computer is only two weeks old, so I would like to know if I should send it back for repair.

I was just going to update this and say that I took my computer to a Genius Bar, and they ended up giving me a new computer. You should definitely send your computer for repair or take it to a store. It is a major hardware mess-up.

If you look down the side of your MacBook your headset jack port will show a red light.
You need to reinsert your head phones a few times slowly to reset.

If this doesn't work, remove all peripheral devices (usb, network, power) and shut the machine off.
Remove the battery. Wait 15 seconds. Press the power button for 5 Seconds to reset the SMC.
Insert battery and restart. Should fix it.

Then reinsert all the other devices and you should be good to go.

I would recommend taking it in. The same thing happened to me, and when I took my laptop into repairs, the guy at the help desk tried a couple of pref. pane tricks (which I don't recommend unless you know what you're doing), then sent it to the hardware guys.

There are a couple of things that could be going on--One, the digital optical switch in the headphone jack (the thing that triggers when you insert headphones so your computer knows to send the sound that way) could be stuck. For me, it was a software problem, and they had to replace the logic board.
Try creating a new account and testing the sound in that one. If the problem persists, it's either a hardware or root library sort of problem. If it's fine, then it had something to do with the preferences settings in your other account.

This issue is exactly similar to the iPhone audio issue. In essence if you are seeing the red light, the sensor that is detecting the jack being used still thinks that the device is still connected. Just insert the device and remove the device and do that about 5-7 times until the light goes away, if not, reset SMC and that should help.

The connecting and disconnecting should resolve the issue though.

Hope this helps.

After the first time this happened i quit putting them in all together. But it was shut down all night and my sound came back on. It is just no fun having a quite computer. No music! but thanks so much! i am going to call the apple people and see what they say.

I had the same exact problem. After a lot of frustration and reading, I simply Shut Down my Macbook. I waited a few minutes and fired it back up. Problem Solved! Try it, maybe you will get lucky too!

Same problem here....any help? Sound only works with headphones in. Can't think of anything different I did to cause this problem.

I have tired this an it will still not work. Do i need to have it taken in? I have had this problem before but it went away after i shut it down.

Do you use headphones for sound? If so, make sure the input is put in all the way in. Put slight force if you have to/