When sound is registered, length is unknown

[milovanderlinden]

The soundJS getDuration function will return 0 on a lot of sound files. Only when the sound starts to play, the duration gets set.

I don't exactly know how this can be fixed. Perhaps a quick play followed by a direct stop? Because in my current 2.0 branch, when you press play once, all times get set.

Before play:

After pressing the play button once: