Apple has pushed a new EFI firmware update v1.8 for Mac mini users (late 2012 models). The update fixes an issue plaguing some users with USB keyboards not being recognized after waking the computer from sleep.
This update is recommended for Mac mini (late 2012) models. This update addresses an issue that may prevent a USB keyboard from being recognized after the system wakes from sleep.
The update comes in at 4.8MB in size and is requires OS X Mountain Lion v10.8.5, OS X Mavericks v10.9.5 or OS X Yosemite v10.10.4 and later. Click here to download it.