Apple Studio Display 15-inch LCD: No sound from external speakers

I have an Apple Studio Display 15" LCD, and I have connected external speakers to it. However, I am not getting any sound from the speakers. What am I doing wrong?
The Studio Display will not provide audio output unless the display is in video mode. In other words, if you are using the 15-pin video connector and monitoring computer video output but not monitoring the C-video or S-video input , you will not get sound. For more information, consult page 50 of the Studio Display user manual.

If you are monitoring the C-video or S-video input, for example from a VCR, follow these steps:
  1. Wire the audio output from the VCR to the audio input on the display.
  2. Use amplified speakers connected to the audio output of the display.
  3. Be sure the amplified speakers have power.

For more information on connecting external speakers and video devices to the display, as well as how to switch video modes, consult Chapter 5 of the Studio Display user manual.
Published Date: Feb 20, 2012