Paradigm Discoloration

I have some discoloration on my speaker's bass/midrange drivers- has anyone experienced this? Speakers- 2003 studio 20's.
No because I keep my grille on (it's designed this way), but I checked for you and no there doesn't seem to be :P Do you mean there's a spot or some sort on the driver or do you mean the colors are a different color from when you first got them?
No, there's an actual stain on the driver...what's weird is that it's also on my center channel too????? I emailed paradigm but haven't heard back...J