Trying to play .mp4 file in beamer, two issues: 1) "play/pause"button not working; 2) how to set a specified time length for the video to play?

Question

I am trying to insert a .mp4 file in beamer, I got it work but two issues arising:

1. the "play/pause" button doesn't work;
2. I want to set a timer that the video only plays a specified time length, e.g. 10s with no looping.

Can anyone help fix my issues? Video attached. Thanks!

\usepackage{media9}

\begin{document}
\begin{frame}{Video example}

\includemedia[label=largecell,
    width=\textwidth,height=0.5625\textwidth,
    activate=onclick,
    addresource=largecell.mp4,
    flashvars={
        source=largecell.mp4
       &sclaeMode=letterbox
    }
]{}{VPlayer.swf}

\mediabutton[
  mediacommand=largecell:playPause,
  jsaction=largecell:{
    try{app.clearTimeOut(tout)}catch(e){} % kill pending timers
    var tout=app.setTimeOut('annotRM.largecell.callAS("pause")', 10000);
  }
]{\fbox{Play/Pause}}

\end{frame}
\end{document}

This is the link for my video