Apple released MacBook Air (Mid 2013) Software Update 1.0 Thursday. The update addresses a WiFi connectivity issue, a screen flickering issue with Photoshop, and an audio problem in the current MacBook Air models.
MacBook Air (Mid 2013)
Apple's release notes:
This update fixes an issue that in rare instances may cause an intermittent loss in wireless connectivity, an issue with Adobe Photoshop which may cause occasional screen flickering, and an issue which may cause audio volume to fluctuate during video playback.
If you have the affected model, you'll find the update in Software Update or Updates in the Mac App Store. You can also download the installer from Apple's support site, where it's a 3.35MB download.