I made this sample. The one I'm looking for has lyrics, but I'm almost certain this is the melody (and how the song starts). The lyrics are through the voice of a young man, and the effect of the voice is like that of Eiffel 65's "Blue", but the waving-effect is not as accentuated... it's a bit more subtle on this song.

http://www.rhomboide.net/music/unknown.mp3