The Playthrough option in the Sound Control Panel is used to set up how a Power Macintosh or Macintosh AV computer plays audio CD's. This option is not available on any other Macintosh models.
Usually the symptom you mention is caused by and extension conflict. Extension conflicts are often caused by older, incompatible system extensions or control panels.
To determine whether this problem is an extension conflict, restart the Macintosh with extensions off by holding down the Shift key at startup right after the Startup tone until you see the message "Welcome to Macintosh. Extensions off."
If the Sound Control Panel looks normal now, you will need to determine by process of elimination which Control Panel or Extension was causing the conflict. (For example, some versions of Suitcase II from Fifth Generation Systems are known to cause this kind of behavior.) *For information on how to troubleshoot Control Panels and Extensions search on the string "init conflict."*
If the Sound Control Panel symptoms continue, remove the file "Sound Preferences" from the System Folder>Preferences folder and restart.
If the symptoms still persist, perform a clean install of the system software. *For information on how to perform a clean install search on the string "clean install."
This article provides information about a non-Apple product. Apple Computer, Inc. is not responsible for its content pertaining to that product. Please contact the vendor for additional information.
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