PowerBook 500: Sound Manager 3.2.1 Static When Recording

I have a PowerBook 520 computer, running System Software version 7.5.5. I just upgraded my QuickTime to version 2.5. Now when I record a sound through the Sound Control Panel, all that gets recorded is static. It did not do this before I upgraded to QuickTime 2.5. What is wrong?
Issue

There is a conflict between non-PowerPC 500 series PowerBook computers and Sound Manager version 3.2.1, which comes as part of the QuickTime 2.5 installation package.

Workaround

Remove the Sound Manager 3.2.1 extension from the Extensions folder, restart the computer, then record the sound.

This issue does not affect PowerBook 500 series computers that have been upgraded to PowerPC-processors with either Apple's or Newer Technologies' PowerPC upgrade cards.

This article was published in the Information Alley on 4 March 1997.
Published Date: Feb 18, 2012