I have a tiled shower that has leaked on the ceiling below. I have already reseated the drain. The grout appears to be OK. There is a small hole at the bottom of the tile by the shower pan about 1/2 inch wide and water comes out into the pan when shower runs. I have cut holes in facing wall and no leak can be seen from the plumbing parts. Any idea what this hole is, or where the water might be coming from?
