It just smells whenever I stop using it. I have 2 QC35 ii and they both smells like sweat. I didn't even use the other one that much. Last time I used it, which was 6 months ago, it smelled fine. I avoid using it when I'm sweating. But turned out it happened again. I just bought the new QC 700 and I'm scared the same thing might happen. I take shower regularly lol they're currently checking for ear pads. I don't want this to happen to my new one and want to take good care of it.