ciao
io per caricare e mandare in loop uso questo:

codice:
//imposto la connessione
var connection_nc:NetConnection = new NetConnection(); 
connection_nc.connect(null); 
var stream_ns:NetStream = new NetStream(connection_nc); 
my_video.attachVideo(stream_ns); 
//stream_ns.play("Flv/"+_root.moviestatus+".flv"); 
//indico il filmato da caricare e mandare in play
stream_ns.play("FLV/video.flv");


// funzione LOOP
stream_ns.onStatus=function(infoObject){ 
   if(infoObject.code=="NetStream.Play.Stop"){ 
      stream_ns.seek(0); 
      stream_ns.play(); 
      } 
};