My wife was complaining about severe headaches for the last few weeks. She was told it was allergies and instructed to take antibiotics but it didn't seem to help. She got another opinion and was asked if she had been exposed to mold lately. After I heard that, I went down to our crawl space and took these pics. I'm interested in constructive comments based on experience with HVAC especially in humid states (i.e. midwest to southeast US). Note: A/C is ten years old - has had strong musty smell starting with second year of use.