Hubby builds/plays bodhrans. He has never encountered the problem you describe. He says to remember that the old joke about never feeding the "goat" anything but Guinness is just that: a joke. Might lemon juice(fresh squeezed) be any help?? Maybe diluted? It has cleansing properties. The problem is to cut the wax/grease and lift off the dirt w/out damaging the 'skin and its tension, if I understand aright. Are there any leather-care experts on the Mudcat or near you who could help?? Would "saddle soap" be wrong for some reason? Wish I knew more.                Tw