From my experience, MDF deteriorates pretty quickly when it's exposed to water, and a water stain remains even after the "wood" has dried. I'm no expert by any means, but I don't think that humidity on its own should affect the speaker finish to that extent. So, if it is water damage from sitting on a damp surface etc., then the MDF should have a visible water stain on it. If my understanding is correct, then I don't know why a warranty replacement or cabinet replacement couldn't be based on a visual inspection at the plant when returned.
Last edited by Powertothepeople; 05/28/11 10:51 PM.
