From the Snowflake Factory, go up the hill to the Adventure's Path and follow it to Goatshire. Find the path behind the cottages in the town that travels up a hill next to a waterfall. Follow it to the top of the falls to find a blue bouncy mushroom. In this area is large tree in the dead end corner, with a woman in a blue dress nearby. Move around the tree to find a small rabbit hole. Drop inside to find the hidden soundboard room.