Apple has released a firmware update which it hopes will fix intermittent screen flickering in some 27-inch iMacs.
The 294kb 27-inch iMac Display Firmware Update 1.0 download is available now from Apple's website.
You'll need access to an administrator account in order to install the upgrade and Apple seems less than confident that the fix will work in all cases, saying: "If you are still having display issues after successfully completing both firmware updates, contact AppleCare or an Apple Authorised Service Provider.
The well documented problem recently caused Apple to delay production of the all-in-one computers and increase lead times on deliveries to an unprecendented three weeks.
If you have installed the firmware update and are still encountering problems please let us know in the comments section below.