Ion-nav-view animation not working... but just for one case!

Ok, this is totally getting me out.

This is the definition of my states:

.state('app.master', {
  url: '/master/{date}',
  templateUrl: 'views/master.html',
  controller: 'MasterCtrl',
  enableMenu: false
})
.state('app.master.sub1', {
  url: '/sub1',
  templateUrl: 'views/sub1.html',
  controller: 'Sub1Ctrl',
  enableMenu: false
})
.state('app.master.sub2', {
  url: '/sub2',
  templateUrl: 'views/sub2.html',
  controller: 'Sub2Ctrl',
  enableMenu: false
})
.state('app.master.sub3', {
  url: '/sub3',
  templateUrl: 'views/sub3.html',
  controller: 'Sub3Ctrl',
  enableMenu: false
})

and this is the “Master” view template:

<div>
    <ion-nav-view animation="slide-left-right"></ion-nav-view>
</div>

Now, when I first call Sub1, I have no animation at all, but this should be right.
When I go Sub1 > Sub2 everything is ok, I get my slide animation.
When Sub2 > Sub3, however, no animation at all is shown.
I’ve tried putting other views in the middle (like Sub1 > Sub 1b), and the animation there is going smoothly.

There MUST be something inhibiting that last animation, but I really cannot get my head over it.
Any ideas on where to search?

I have been facing the same issue as well. Sometimes the animation works and sometimes it doesn’t. Same exact scenario, anyone with answers?
Thanks & Best Regards,
Jacob Sebastian