Issue with ion-slide-box

First, I have 2 slides (slide 1 and slide 2) in the ion-slide-box, then after a timeout of 2 secs, I replace them with 2 new slides (slide 3 and slide 4).

Looks like $ionicSlideBoxDelegate.update() is not rendering all the slides. Only Slide 3 is rendered properly, Slide 4 is not. What might be going wrong?

Thanks for your help.