VirtualScroll + Async = Blink!

Hi,

I am trying to add rows dinamically to my virtual scroll using an angularfire2 observable and the async pipe, but every time I add new items to the list, first the list blink two times and then refresh with the new item.

<ion-list [virtualScroll]="myList | async">
    <ion-item *virtualItem="let item">
    {{ item }}
   </ion-item>
</ion-list>

Any help?

Thank you.