Wood trim separating at the top of your brick could be a sign of a foundation problem.
Here is a photo of trim separation. This problem was not caused by poor carpentry.
Corner trim separation is a tell-tale sign of a foundation problem.
As the concrete slab drops on an outside corner, the brick veneer walls in that area remain somewhat perpendicular to the slab, while the trim remains affixed to the roof system. The result is that the brick veneer pushes outward on the trim.
One trick for hiding the foundation problem is to caulk and paint the trim. A thick caulk joint at what should have been a perfectly aligned carpentry corner is a dead give-away of a foundation problem.