Anyone have experience of a leaking shower? We have had 2 plumbers round. One said it was the sealant, so we redid that. The second said the tiles needed regrouting so redid that (both sealant and grout were already in quite good condition but still redid on plumbers' advice). DH had a shower this morning and it didn't leak but DS has just had one and once again it is leaking through the ceiling into the sitting room. Does anyone have any ideas?