Getting Buzzer to play stock Casio frequencies

[matt-8319]

I'd like my Sensor watch to play the stock Casio tones, especially when cycling through the faces. I have measured the 91W Casio 'beep' and it is approximately 1024Hz. If I add the factor in (1000000 / 1024) 977 to the buzzer frequency list I just get a click upon playback.

Is there a hardware limitation that prevents arbitrary frequencies or have I done something wrong in the code?