I have water leaking downstairs when I run my shower. The pan was replaced in May. I believe the pan was made of rubber, and installed under a tile floor, not a prefab shower. The leak only happens when I run the shower. I found out how I can check to see if its a pipe or something, but have been told if it is in the shower pan, there may be some easy fixes. What might those be? I am going to cap the shower this weekend and see if the leak is in the pipes, but am curious about fixes for the shower pan