That is not possible with any method I know of.
Oh no! Leaving the button in the 'STOP' state will look lame.
I have about 200 audio files to place into my EPUB.
Is there any way of controlling the look of the embeded media player? All the options in the Media panel are really lousy looking and with poor functionality. Surely this has been done before?
For audio you could create your own buttons, but beyond that you're going to be tied to however the reader handles the media.
What you see in the media panel is irrelevant. Most of that is base on SWF output.