It seems like it only happens in Chrome and Safari.. not Firefox. I\'m using it with the foundation responsive framework so I\'m not sure what to do about setting the height.
You should make sure you preload all imagess before you call isotope method, here is real world demo for this: http://gbin1.com/gb/demoviewer/360/06242ba0-40a1-45fd-946f-cc89e0df64c9/index.html.htm , you preload images with jquery.imagesloaded.min.js plugin, then call isotope , content won't get overlapped.