Midas' ass's ears or Midas touch or the golden touch.
Apollo and Pan entered into a musical contest. When Apollo was judged victorious by the mountain-god Tmolus, Midas, the king of Phrygia, disagreed. For his lack of perception Apollo transformed Midas' offending ears into those of an ass. To have ass's ears means that one lacks true musical judgment and taste. On another occasion, the god Dionysus granted Midas' wish that whatever he might touch be turned into gold. To his despair, Midas found that even as he put food and drink to his mouth it was transmuted into gold. Dionysus granted him relief by telling him to bathe in the river Pactolus, whose bed become golden. To have the golden touch or Midas' touch means to be successful in any endeavor.