Take the 2-minute tour ×  How do I get my sound working again?
It works with Headphones, but when I unplug the headphones a red
light is coming out of the headphone jack and I can't adjust the
volume on my Macbook Pro.  share|improve this question add
comment  2 Answers  up vote 10 down vote accepted  macRumors
ref: No sound out of MacBook speakers & red LED in Headphone
jack. The red light is probably because its a Mini-TOSLINK port.
There is a metal prong in the jack and sometimes it can be bent,
causing the digital audio to be turned on when it shouldn't be.
The problem is there is a switch in the jack that tells it if
you have a mini headphone plug or an optical plug plugged into
the headphone port. The problem is when you remove the plug, the
jack doesn't know it and keeps shining the red light to talk
with the optical. This disables the internal speakers and you
see digital out instead of internal speakers in the speaker
conrtol panel. Plugging and unplugging the speakers may get it
working right for