Loading all items when row details are expanded in datagrid wpf.

[IG0111]

When I select a row in the datagrid, details are displayed. This causes all pages to load.

public Task<PagedSourceItemsPacket<T>> GetItemsAtAsync(int pageoffset, int count, bool usePlaceholder)

This method is called until all pages are loaded.

Do you know how to solve it without disabling row details on selection?

I am using .net 4.5.
Control have this properties set:

CanContentScroll = true
VirtualizingPanel.ScrollUnit="Pixel"

If i leave scroll unit to "Item" than everything works fine.