Mac mini EFI Firmware Update 1.7 is a 4.53-megabyte download now available from Apple. It's compatible with the late 2012, Ivy Bridge powered Mac mini models released by Apple this fall.
Apple said the update, recommended for all users, will address HDMI flicker issues. Users must not disturb or shut off the power to their Mac mini while the firmware is updated.
Display flickering issues with the new Mac mini have been well documented in a popular thread on the Apple Support Communities forums. There, users have reported that the video from their Mac would cut out for a short period of time before returning.
The flickering issue happened relatively infrequently ??about once every few hours, users said. However, it happened often enough that some users noticed it on a daily basis.
Users experienced the issue with a wide range of monitors, and also when using an HDMI to DVI converter.
The Mac mini was updated with Intel's latest Ivy Bridge processors and up to 16 gigabytes of RAM in a new model released in late October. The desktops also feature Intel HD 4000 graphics, Bluetooth 4.0, and up to 1 terabyte with a hard disk drive, or 256 gigabytes with a solid state drive.