When I specify infill angles... say for example 0, 45, 90, -45, the infill honors those angles but the top/bottom layers always just print at 45, -45.
Also, you might need to specify the top/bottom infill angles separately because if you have a hex infill pattern the same angles don't apply.
Problems occur on models where you have a hex infill pattern and then you come to a top surface that has a cutout feature. Imagine a smaller cube cut from the top surface of a bigger cube. As the first top layers of the inner cut start to print, the edges only stick to the edges of the hex pattern. Normally, if you had a 45 degree offset on the next layer, it would only take 4 layers before plastic formed a good square on the hex pattern. Since there are only two layers however, when you start printing the walls most of the time you still have holes between the infill hex and the edge of the walls.
Result = crappy print.
Easy fix to just print more angles on top/bottom layers.