Recipe(tried): Cream Cheese Pound Cake (Top Crust Separates When Cooling)

CREAM CHEESE POUND CAKE

3 sticks (1 1/2 cups) unsalted butter, softened
1 (8 oz.) pkg. cream cheese, softened
3 cups granulated cane sugar
6 eggs
2 tsp. extract
3 1/4 cups cake flour

Preheat oven to 300 degrees F.

Beat butter and cream cheese on medium with Kitchen Aid stand mixer for 5 minutes then add sugar and beat an additional 5 minutes. Add eggs one at a time and only mix until yolk disappears. Add extract(s). Add sifted cake flour using hand until blended. Put in 10-inch tube and bake for 1 hour and 30 minutes.

After it is done it looks fine when I take it out of the oven but once it starts cooling, the top crust separates from the rest of the cake. When I try to take it out of baking pan, the crust crumbles and is very hard and flaky. Everytime it does this. Excellent flavor but the crumbling crust takes away from the presentation. Please advise what I need to do. Thanks.