IBoutlets nil in swift when using storyboards

In one of my ViewControllers, when I get to viewWillAppear, all my IBOutlets are nil, I tried looking at @matt`s solution but it works for nibs not in Storyboards.

This is only a problem when I run the app on devices that are on iOS 7. It doesn't happen on other devices.

Does anyone know why all my IBOutlets in that viewController is nil (notice that other viewControllers works fine.)

Edit: Tried creating a new ViewController in the storyboard, with some labels, and a new TestViewController.swift file, and connecting them, still getting nil values, please understand that the rest of the project works just fine.