Apple has released a couple of firmware updates for the AirPort base station and Time Capsule Wi-Fi units. The updates fix a number of features, including overall stability, settings issues, and AirPlay compatibility (the iTunes update earlier this week also addressed AirPlay problems).
The specific problems addressed are the following:
General fixes to Wi-Fi base station stability
Fixes some issues with AirPlay streaming
General fixes with USB interoperability, including connection to external storage devices
Fixes some issues with NAT port-mapping settings
Disables TKIP security with 802.11n rates per the Wi-Fi Alliance specifications
In addition to the firmware updates, Apple has released new versions of AirPort Utility, which it recommends you install before applying the firmware updates.
To update your firmware, follow these steps:
Download and install the latest version of AirPort Utility:
Open AirPort Utility and check for updates by choosing "Check for Updates" from the "AirPort Utility" menu.
Select your Base Station or Time Capsule.
Click the "Update Firmware" button in the middle of the Utility window.
At this point the updater will download the firmware and then prompt you for your base station's password. After you provide your password, follow the onscreen instructions to complete the update.