A thread was started on Apple's official discussion forums in October for problems with the new 27-inch, LED backlit screen, which sells for $999. Since then, it has grown to over 200 posts and 15 pages as of Wednesday, with numerous users reporting the same problems, while other threads (1, 2) have also been created.
Some of the new Cinema Displays completely lose sound after a period of use. Users said the only way to fix the problem is to unplug the display, and then plug it back in. But the temporary fix does not prevent the issue from returning.
There are also issues with the response time of volume control on the keyboard. Some said they experienced delays of 6 to 7 seconds after pressing a key to change the volume.
Some who contacted Apple support were sent replacement displays, but those also exhibited the same problem. Some who contacted support were told that Apple is aware of the problem, but the company could not provide any details on a potential fix.
Some said they have experienced the same issues while running the display with Windows as well, suggesting it is not a software issue related to Mac OS X. Some have found success by changing audio settings, and have suggested the problems are related to USB audio, as newer Macs that send audio over the Mini DisplayPort are apparently unaffected.
"Audio becomes disabled and I cannot even select Display Audio (USB) audio from Sound preferences pane," user hmss007a wrote. "The only options available are Internal Speakers and LED Cinema (DisplayPort), which doesn't work."
Before it was released, Apple issued a software update for the new Cinema Display. But that update simply added the ability to adjust ambient light sensor settings in the System Preferences pane.
"System power setting re-set does not fix it, nor does unplugging mini-display port," user jeremypk wrote. "Very disappointed. Puzzling because the sound did work at first (at least after installing the recommended software patch from Apple), and sound seems to be dead completely now. I hope Apple is reading this."