We have had a similar experience with Milgard windows. We built a new house in 2007 and installed all Milgard windows. The first to go was a window in the garage. The inside pane on the slider shattered. We replaced it at our expense. The next to go was the outside fixed pane on the same window. That was followed by an upstairs window of the same size. And most recently the outside pane on a bedroom slider exploded with a loud bang. My wife was sitting directly below when the window blew. All of the windows were the same size, 24 by 24 inches. I would like to caution anyone who is considering installing Milgard windows. Milgard does not stand behind their lifetime warrantee for spontaneously shattering windows.