I live in Miami, FL. When running the air conditioner, part of the air flow escapes through the defrost exits on the dashboard. So when it's humid outside, this problem causes the front windshield to fog up. If I put on the wipers, it clears the issue temporarily but spreads the humidity on the windshield. So, the problem gets worse when the wipers are turned off. Has anyone encountered this problem. If so, what is the solution other than my mechanic taking apart the dash to fix the issue.

 

A similar bug was caused by misfunctioning of 2 valves/flaps (may be servomotor).
Another was fixed by reset to the basic setting of the air conditioner at the Car Dealership.
Third not really similar case by interior air filters.