tiles popped (8 total, two rows of 4) the first time about 3 years ago. then about 6 months ago, the entire dining area in my house popped.
when you knock on the tiles in the kitchen, you can hear the hollow sound of nothing between the tiles and the ground.
i was told by several people that this is due to cheap thinset that was used years ago (my house is closing in on 15 years old).
sucks, but i'll have to retile my entire house...first need to sell more weddings as i need a new floor, new roof, new kitchen, new bathroom, new ceiling, new doors, new windows....*sigh* - home ownership!
seems my house, like me, has reached the end of its shelf life! Time for reconstructive surgery!!!