Well, this is a shame.. Apparently the sample rate of the AudioContext (for some people 48 kHz) isn't definable (it should be 44.1 kHz here), which makes this a tough thing to fix. For me, it works in osx but not in windows 8 (bootcamp).

I found this: https://github.com/WebAudio/web-audio-api/issues/300

Apparently it's not implemented yet?