Apple released Hard Drive Firmware Update 2.0 late Wednesday afternoon to address an issue where beeping sounds emit from MacBook Pro hard drives. The issue affects MacBook Pro models released in June 2009 with 7200 RPM hard drives installed.
The updater installs an application called Hard Drive Update in /Applications/Utilities. Running the app will install hard drive firmware version 0007APM2.
The update requires Mac OS X 10.5.7 or newer, and is available as a free download at the Apple Support Web site.