Tone.js chords sometimes sound tinny

[pganssle]

This one is really hard to debug — the Tone.js chords sound great to me when I use headphones on my computer, but they sound super tinny when I play them through the tablet speaker. It doesn't seem amazingly consistent — I've been able to get tinny sounds on the computer sometimes, but not reliably (and sometimes only in the "game mode" and not the trainer).

If anyone can figure out how to debug that would be great, because my son finds it very hard to hear the sounds when they are tinny like that.