If you think about it, you'll realize that very few bicycle helmets will reduce wind noise. To reduce wind noise, there has to be something to alter or block the wind from reaching your ears. Some aero helmets covers the ears, but most regular helmets do not cover the the ears. The helmet isn't so much making the noise as is the air rushing past your ears.
Personal experience indicates there is much more to it than simply covering the ears. Going from the Giro Aeon to the Bell Gage the wind noise went from deafening to just annoying. Still want to bring it down to the "mild/non-annoying" level but it was a significant change.
The strap thing is interesting but I'm not sure how big a deal that is if I always wear sunglasses over straps and have my chin strap done up pretty darn snug. Does this imply that a heavier strap *Kask* may not flap as much reducing noise?
The reason I specifically included the Aero Helmets is because in reviews of both the Evade and Air Attack I have seen multiple mentions of reduced wind noise and was wondering if there were any other real world examples or direct comparisons for people that own other helmets too *Kask Mojito or Prevail*