I downloaded an application that uses the sound card and provides AC osciliscope capabilities (no DC). With no speaker (load) attached I see a spike when the sound starts and a matching inverted spike when the sound stops and since I don't think it does DC I expect it's shifting to a TTL high during this period. There is no detectable waveform present. When I switched back to the note 157 (white noise) I DO see a square wave form that is random in nature. Still no clue here why it's not producing any noise for the 1-128 notes.