Crashes in linq query

[fluter01]

The CarouselView crashes when swipe half way of the view item and then releases, it looks in this case visiblePositions will be holding more than one item, so it crashes in the linq's Single query:

12-12 10:00:28.431 I/MonoDroid( 3010): UNHANDLED EXCEPTION:
12-12 10:00:28.494 I/MonoDroid( 3010): System.InvalidOperationException: Sequence contains more than one element
12-12 10:00:28.494 I/MonoDroid( 3010): at System.Linq.Enumerable.Single[TSource] (System.Collections.Generic.IEnumerable`1[T] source) [0x00070] in :0
12-12 10:00:28.494 I/MonoDroid( 3010): at Xamarin.Forms.Platform.CarouselViewRenderer.b__8_2 () [0x00011] in <3867cb0a879d490a9a2604d76def86f4>:0
12-12 10:00:28.494 I/MonoDroid( 3010): at Xamarin.Forms.Platform.CarouselViewRenderer+OnScrollListener.OnScrollStateChanged (Android.Support.V7.Widget.RecyclerView recyclerView, System.Int32 newState) [0x0003d] in <3867cb0a879d490a9a2604d76def86f4>:0
12-12 10:00:28.494 I/MonoDroid( 3010): at Android.Support.V7.Widget.RecyclerView+OnScrollListener.n_OnScrollStateChanged_Landroid_support_v7_widget_RecyclerView_I (System.IntPtr jnienv, System.IntPtr native__this, System.IntPtr native_recyclerView, System.Int32 newState) [0x00011] in <00ef854e109241db9d853f1dd4d69cd9>:0
12-12 10:00:28.494 I/MonoDroid( 3010): at (wrapper dynamic-method) System.Object:b132f440-26d6-4af5-88e0-df5ad0f45ec7 (intptr,intptr,intptr,int)

I'm just using the demo project at https://github.com/jamesmontemagno/Xamarin.Forms-Monkeys/tree/master/Monkeys-CarouselView