The System 7.5 Update 1.0 sets the alert volume to maximum during installation. Follow these steps to lower the alert volume:
Step 1
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Under the Apple menu, choose Control Panels.
Step 2
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Double-click on the Sound control panel.
Step 3
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From the pull down menu, choose Volumes.
Step 4
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Use the slider bar to adjust the sound to a desired level.
If you have a Macintosh Centris/Quadra 660AV or Quadra 840AV, some system alert sounds may not play correctly with the Alert Volume turned down. In these cases you will have to keep it at full volume.
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