My mom has a pair of white Paradigm Atom speakers and got something all over the speaker grill. I think she had a plant on top of it and overfilled it. Anyways, I've looked at the speaker and can't determine if the grill comes off or not. I've pulled on it some, but its either permanently attached or a very tight fit and I don't want to break it. Anybody have any suggestions on how to clean the grill off?