To find the flute playing faun, you must go to Fauns' Thicket on Galen. Fauns' Thicket is a delve on the western side of the island.
Once in the delve you must find your way to the path in the middle of the map that goes in the northern direction. When you follow this path you will find yourself in a cave-like structure. Follow this cave. Once you exit the cave, immediately turn right. The Faun should be right there before you.