5 Replies Latest reply: Nov 5, 2011 2:29 PM by TheSmokeMonster
ACr8on Level 1 Level 1

my sound randomly stopped working, why i try to turn it up on the top of my computer in the bar it doesnt let me change the volume and it is greyed out. when using my keyboard to turn it up it doesnt let me and there is a circle with a line through it (the no symbol) that shows up.

it works with headphones and there is sometimes a red light coming out of the headphone jack

what do i do?!

my computer is brand new and the sounds not working already!

MacBook Pro
  • TheSmokeMonster Level 4 Level 4




    after reading the trouble shooting follow the instructions for your specific computer to do an SMC reset.


    Edit: responded too soon!


    That red light is the digital optical signal being sent out! if the SMC reset doesn't fix your issue go to apple immediately. This means that the computer things a MiniToslink is in your machine and shouldn't be on. It could be a sign of a hardware malfunction. if it's brand new, go to apple and they will repair it free of charge.

  • WALTER-MILANO-ITALY Level 4 Level 4

    The headphone jack is also used for digital output.

    If you see redlight there it is probably setted to use a digital output instead of normal.

    May be this disconnects the internal speakers.

    I'm tryng to find how this could be changed.

  • TheSmokeMonster Level 4 Level 4

    Walter, thanks for repeating my suggestion. To look in your system to turn off digital encoded output, you go to audio midi setup, and select the system audio and change it to the correct output.


    However this is usually automatic and won't stay on unless the hardware is in the socket. Which again brings me back to thinking it's a hardware issue and you should go to apple store immediately.


    should look like this:


    Screen Shot 2011-11-04 at 6.14.44 PM.png

    yeah, and you can only select encoded out if you have the miniToslink in the computer.

  • WALTER-MILANO-ITALY Level 4 Level 4

    Now it is clear.  While tring to answer Acr8on and before seeing your answer I also had a look into midi but I was not able to understand. Now it is clear: without a digital harware connected to my Mac I could not find any possible way to select or deselect a digital output. Thanks for your followup: as often happens with Apple software the possible choice is presented only if the hardware is connected or even if the software support the choice.

    Therefore your suggestion of a possible harware fairlure was really perfect.

    Thanks again.

  • TheSmokeMonster Level 4 Level 4

    The OP, in this case, should do an SMC reset because it purtains to volume controls ontop of other things.