Q: When hot outside, bad odor from vent when on

When the weather outside got hot, I had my vent blowing (not the air conditioner) and there was a very bad smell. So bad that I got nauseated. I took it to the dealership 4 times for this same odor problem from the vent and no one knows what the smell is, nor how to get rid of it. They ran it through an Ozone cleaning system and deodorized the A/C unit 3 times (even though I don’t think it’s the A/C). There is also a loud buzzing sound that’s coming from the driver’s side window. This happens when the wind blows on it. There is also a clicking sound that I think is coming from the passenger’s side which is near either the seat belt or the rear passenger’s side door. What do you suggest?