Vivosmart 4 heart rate is a pinball machine since the update 12 days ago

My friend who sits next to me in spin class has her heart rate jumping all over in class.  She just texted me she got 190 walking through the mall.  It is anything but accurate since the last update which just happened to contain a new heart rate algorithm.  It was fine before this update.  The update was automatically loaded onto her watch from Garmin Express.