My name is Bill from Iowa. I bought a new propane smoker, Masterbuilt I believe. Did the whole cure thing and smoked a couple of times and did OK. Then I tried to get tricky and put some wine in the water pan to maybe add some different flavor to the meat. Backfired! As it was smoking it put a black film all over the meat. I cleaned the water pan and grates and all that but the next time I tried smoking it did the same thing and I just put water in the pan. Is there something else I need to do to stop this from happening? I need some advise please.