I started out with testing with different values. The empty String seems to work fine except for some very low note that can be barely heard without earphone.
Test with empty string solution 
This gave a hint that lowering the note frequency may be a solution. I then tested out in P5. Then I googled the lowest value Tone accept, which is E0. Unfortunately, the low note problem still exists.
While discussing with Ying, he suggested 0 may be helpful. Yet just like the two tests before, I can still hear a low note beated with my earphone.
Even though none of the three is perfect, I think they all can be the solution for this since one can bearly hear the three notes and they all have the music played as wanted.