Loading multiple instruments on Firefox tends to cause an unknown error while processing while processing decodeAudioData

If I have a setup like this

MIDI.USE_XHR = false;
MIDI.loadPlugin({
	soundfontUrl:"http://gleitz.github.io/midi-js-soundfonts/MusyngKite/",
	instruments: [0,4],
	onsuccess: function() {
		var startingPoint = MIDI.getContext().currentTime;
		MIDI.noteOn(0, 50, 127, startingPoint);
		MIDI.noteOn(4, 55, 127, startingPoint + 1);
	}
});

I will occasionally get the error An unknown error occurred while processing decodeAudioData.

Sometimes, this can result in an "out of memory" exception or outright crash the browser

Meanwhile, I could load similar code on Chrome, loading 5 instruments, and not a single failure occurs.

This was a Firefox bug that was fixed.