try switching the cloth to something lighter....
I dunno, but the cloth on my speakers (camry) had gotten dirty, and I didn't like the grey color, so I ripped them all off and put black polyester over the plastic covers instead...really thin stuff that doesn't affect the sound, but thick enough to not be able to see thru....
try something like that....cuz the cloth that comes on top of the speakers is pretty heavy, allowing it to make sound....I think lighter cloth shouldn't make sound...if that's really the case....
good luck!