Blisters in Prints

[earthball]

I am running a Mars Pro with standard grey resin and experienced some issues with occasional "blisters" or extra cured spots in some tight spots. Most of the print comes out great, but every single one has had a problem with this to varying degrees. For these parts (model of jet engine), I have been trying to print directly on the build plate, but figured there may be some air bubbles under the FEP being trapped by the outer ring of these parts . The ring where the blisters occur is only about .25" (~6mm) in diameter. I tried printing the part with a 15deg angle and got similar results. Print settings are 0.04mm layer height at 6s exposure.

Any ideas on how this issue could be solved?