Edit: After half day, my wife’s Mac started having the same problem. I have then applied the solution that I found in the Apple
Apple Releases iOS 6.1 Beta 2 To Developers
Apple has just released iOS 6.1 beta 2 ,build 10B5105c to developers. If you have an iOS Developers account you can download the beta from the developers centre or if you are already on iOS 6.1 beta 1 you can update over the air.
Alongside iOS 6.1 beta 2 Apple also released an update to Apple TV software and Xcode 4.6 Developer Preview 2.
- apple news