Upstairs shower leaking onto downstairs ceiling. I have had three call outs to diagnose. First call revealed shower head neck was caroaded and leaking. Replaced and seemed to cure the problem. Few months later noticed more leaking in same place. Second call diagnoses was grout needed to be replace. Re-grouted, sealed and chalked. Still leaking. My shower is 3 x 3. Three sides are mable slabes with 2 x2 mable squares on floor. Shower plumbing is on toilet side wall. Thinking I should either cut hole in wall to exposed shower head and hot/cold plumbing or cut hole is living room ceiling so see if I can determine leak source. Thanks for any advise you can provide