Capcom recommend playing Nazo Waku Mansion with headphones or earphones, and for good reason; the game is focused on 3D sound. You can listen to some audio samples of this in this older post.
Instead of using buttons, Nazo Waku Mansion is played in every other way imaginable. Games are played using the touchscreen, the tilt controls, and even speaking to characters or giving commands through the microphone. Capcom have the game slated for release next month on August 4th.