Check if your Volume Settings are OK.
You can use the Volume button which
is generally on the wright bottom side of your screen on the start
tool bar to access the
Volume settings.
Double Click to open it.
See if the volume settings are OK. You should
look at if your Play Control or Wave are
muted or just decreased volume. Those are generally first two balance
bars. If the Mute box are checked uncheck them.
Check
your QuickTime Players Settings
This apply if you can hear sounds
from other applications such as Media Player or your MP3 player
but not from
QuickTime.
First Open your QuickTime player
Then go to Edit - Preferences -
QuickTime Preferences menu item.
A dialog box will open
Select the Sound Out option from the drop down
menu.
Select the waveOut option
instead of the DriectSound from the Choose a device for playback drop down menu. Then close the dialog box. Try to play the file again.
If this won't work Check out the QuickTime Web site for more Troubleshooting
tips. http://www.info.apple.com/usen/quicktime/