After reading several comments on this message board, and my own experiences with my watch as well as my wife's watch, it is my opinion that TomTom has a design flaw in their Multisport, Runner, and probably the Spark watches that causes the waterproofing seal to fail. Both of our watches developed condensation below the glass screen and shortly afterward both watches failed to respond to button pushes or computer connections (including recharging). My wife's watch failed while under warranty, but it appears that most (including my watch) fail after the warranty period expires and TomTom will not offer a solution other than buying another watch. It clearly states on the underside of the watch that it is "Water Resistant 5ATM". Until TomTom offers a re-design or repair of this flaw, I would be hesitant to purchase any of their Multisport or fitness watches.