Air coming through the front door speakers

[lofty]

when im on the motorway im sure i can feel air entering the car through the door mounted speakers, this must be doing the speakers (which i have upgraded to Alpine 13cm 2 ways) i have had soem problems with them after installing, and when i did install them i sealed them flat to the door with silicone for extra sound quality,

any ideas,

 

[towser]

I was always told not to use silicon on speakers as it would damage them! As for the draught - no idea!