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Well, here's why your deflectors didn't work:
"Wind rush noise is produced even if the flow is attached everywhere on the vehicle surface because the boundary layer flow is turbulent over most of the car. Hence, it is not possible to achieve zero wind rush noise. However, if the flow is separated, the wall pressure fluctuations are more intense by a factor of approximately ten, and much more wind rush noise is generated.... Usually the most serious wind noise problems are associated with the A-pillar area flow.... The flow velocity around this corner can be 60% higher than the free-stream air speed." Callister, John R. and Albert R George, "Wind Noise." Aerodynamics of Road Vehicles, ed. Wolf-Heinrich Hucho (Warrendale: Society of Automotive Engineers, 1998): 347-48.
Their suggestions to address it:
-radius of A-pillar as a whole should be as large as practical
-exposed rain gutters should be avoided
-auxiliary seal is needed to seal the A-pillar gap, and should extend down to where the door meets the body
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