When you play a file with RealPlayer, the file plays but there is no audio output.
If the file you are trying to play is corrupt, you may not hear sound when playing files with RealPlayer for Mac OS X. To check your player, try playing other files that are not corrupt. If your player doesn't play other files as well, try adjusting your computer's sound configuration.
Confirm that Mute [ ] is off so that it looks like: and that the volume slider is not all the way to the left (turned down to 0). If RealPlayer is not set to mute, click to restore sound.
To rule out a problem with the file, try playing sample sound files:
Open service.real.com/realplayer/test in your web browser.
Click the links that match your connection speed. Dial-up modem users should choose the 28 K or 56 K links.
If the sample sound files play and you have audio, the problem is most likely with the specific file you were trying to play.
If the volume settings for your conputer are muted or set too low, you will not hear sound while playing the clips.
From the Apple menu, select System Preferences.
Under Hardware, select Sound.
In the Output, ensure that the Output volume slider is set to high (to the right of the slider, and that the Mute option is cleared.