I have a large area painted a dark blue and all the drywall compound is creating a white film. Even every detail of the corner bead is visible. The area was built about 20+ years ago and was painted (have no idea if it was primed); we purchased the house 12 years ago and had it repainted. About 5 years ago this problem started. The white, powdery film washes off easily, but always comes back days or weeks. Any ideas why this is happening or how to get rid of it?
