One thing you might want to try is making your slider created with createSlider a child of the audio-controls div by calling audioSlider.parent('audio-controls');. However, be aware, there seems to be something special about the canvas element that makes it appear above other elements in the stacking order. So you might want to set the z-index of audio-controls to 1 (alternately setting element positions to 'relative' does seem to magically pop them above canvas in the stacking order). CSS is bonkers sometimes 
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