Apple today released Mini DisplayPort to VGA Firmware Update which addresses intermittent flickering and compatibility issues such as no video on some external displays when using the Mini DisplayPort to VGA Adapter on your Mini DisplayPort enabled Mac.

The Mini DisplayPort to VGA Adapter firmware update will be downloaded to the Utilities folder and will automatically launch to update the firmware on the Mini DisplayPort to VGA Adapter.

The Mini DisplayPort to VGA Adapter must be plugged into your Mac and a compatible VGA display. The Mac power adapter must be plugged into a power outlet.

Mini DisplayPort to VGA Firmware Update is available via Software Update and also as a standalone installer.

More information and download link (11.4MB) here.