I don't quite understand how this attack works. They are constructing a simple audio synthesis graph and rendering it for a few seconds. But since all the aud

I don't quite understand how this attack works. They are constructing a simple audio synthesis graph and rendering it for a few seconds. But since all the audio processing happens in the browser, without OS involvement, how can the fingerprints be different between say 64 bit Firefox browsers running on 64 bit Windows? I can understand differences between different browser binaries, since optimizations can slightly change the output due to floating point order of operation, but can a particular browser binary generate different fingerprints?