How to restore the startup sound
But what if your startup chime has deactivated on its own, completely unintentionally? There are a few things that you can try. The first thing is to ensure that the volume on your Mac's volume is not muted when you shut the machine down. On some models of Mac, if you boot your Mac with the volume muted, the chime will not sound.
The second fix that you can try is resetting the PRAM on your Mac. To do this, perform these steps:
1. Shut down your Mac.
2. Hold down the Command, Option, P and R keys.
3. Press the power button, and continue holding the keys.
4. When the computer reboots a the second time, release the keys.
Zapping the PRAM resets things like volume, display resolution and startup disk settings.
When the MacBook Air reboots the second time, you should hear the chime. If not, then there's one more reset that you can perform: the System Management Controller (SMC) reset, which is done by performing these steps:
1. Shut down the computer.
2. Disconnect the computer from any external power sources, and remove all connected accessories.
3. Hold down Shift, Control, Option and Power keys.
4. After a few seconds, release the keys all at the same time.
5. Press the power button to turn on the Mac.
This resets the System Management Controller, and may also spark life back into the magical start up chime. If that fails, however, you may need to visit your local Apple Store to see if another issue ails your Mac.
It's been a valuable trouble shooting tool on occasion so it seems inevitable that Apple would deep six it.
Video comes on, video dies (unit reboots), video comes back. Not too difficult.It's been a valuable trouble shooting tool on occasion so it seems inevitable that Apple would deep six it.
Wonder how you tell if the command option p r boot combo has been held down long enough?