Apple Pro Speakers: No sound from speakers

Symptom

There is no sound from one or both of the Apple Pro Speakers.

Solution

Follow these steps:

1. Push on the Apple Pro Speaker jack to make sure it is firmly inserted into the Apple Speaker sound output port
• The Apple Pro Speaker jack has two detents. You should feel them as you push the jack into the sound output port. Giving the Pro Speaker's connector a slight twist while inserting it into the sound output port may make a better connection.

2. Verify the speaker volume and balance are set appropriately in the Sound control panel. Check to see if sound has returned.

3. Reset the Parameter RAM (PRAM) by following these steps:

• Shut down the computer.
• Locate the following keys on your keyboard: Command, Option, P, and R. You must hold these keys down simultaneously in this step.
• Press the computer's power button and then simultaneously hold down the Command-Option-P-R keys. You must press these keys before the gray screen appears.
• Continue to press the keys until the computer restarts twice, then release the keys.
• The parameter RAM and the non-volatile RAM in your computer are reset to the default values. The clock setting is not changed.

4. If the computer emits normal startup sounds from the speakers, yet there is no sound present once Mac OS has started up, reinstall the system software from the Mac OS "Install" disc that came with your computer.

If the symptom persists after following these steps, call Apple for assistance in replacing the speakers.

For more information, see "Macintosh: How to Reset PRAM and NVRAM".