The issue is it only takes the briefest encounter with a magnet and the valve is impacted. The magnet lifts the adjustable mechanism and moves it in the direction that the magnet passes. My children actually lay there heads by the iPad in the evening when watching videos. My niece has a programmable strata valve that was being inadvertantly reprogrammed. My brother is certain that the iPad 2 was the culprit as he has not had the issue since being made aware of the magnets. I agree with the science expressed in earlier posts but the real world with children is not quite so simple. I do appreciate everyone's insight.