video is streamed but is not working together with the player skin(?)

nc = new NetConnection();
nc.connect( "rtmpe://localhost/vod" );
nc.onStatus = function( info )
{
    trace( info.level + ": " + info.code + " " + info.description );
   
    if ( info.code == "NetConnection.Connect.Success" )
    {
        ns = new NetStream( nc );
        ns.onStatus = function( info ) { trace( info.level + ": " + info.code + " " + info.description ); }
        ns.play( "sample" );
    }
}

nc.stat = function( a, b ) {
    trace( "stat called " );
    // if you return anything else (or don't return anything at all)
    // stream access will not be turned on, so playbacks will fail
    return a*b;
}

This is my code that i have inserted into the first frame(?) of the fla file.

When I use the swf in a html web page, i can hear the video but I can't see it and play skin cannot control the video.

This is also a part of a security token code which i'm implementing on the client-side.

Help Please?