So, my wife and I bought our house back in 2009. This past summer, my wife painted the ceiling with Zinnser Primer + Ceiling paint because she noticed the original paint was cracking. About a month later, we notice the paint on the ceiling starting to crack again. Where it started to crack, we pulled on the paint to see what was under it. When we did, a huge sheet of paint came off, all the way to the bare drywall. Come to find out, none of the paint is sticking to the drywall. However, it is sticking to the areas where mud was applied. Has anyone see this before?