InvalidStateError after refreshing the page a second time

[nise]

If I open an refresh the webpage on a server Firefox comes with the following Error:
"InvalidStateError: An attempt was made to use an object that is not, or is no longer, usable"

This error might be cause by accessing an audio file before it has been loaded. Event listeners should be used in order to avoid this:

myAudio.addEventListener('canplaythrough', function() {
    // do things with the audio like calling currentTime, duration, seek, ...
}, false);

[timobaumann]

can you turn this into a patch or make a pull request? thanks.