A few minutes ago Apple released a minor firmware update for the LED Cinema Display to address audio issues experienced by users on the 27-inch model.
This Firmware Update addresses intermittent audio issues some users have experienced while using the 27-inch LED Cinema Display.
The updater application will be installed in the /Applications/Utilities folder and will be launched automatically. Please follow the instructions in the updater application to complete the update process.
The update is available now in Software Update or on Apple’s website. A support article detailing the intermittent audio issues is available here. The issue has also been widely documented on Apple’s discussion boards.
[Thanks, Greek iPhone]