When you play HTML5 video (eg, youtube) in the following system environment, system (OS) is forced to restart the time that has elapsed much about 5 minutes.

* Windows 7sp1
* Intel Core i3 3225 HD4000
* Intel H61 Express Chipset
* RAM 8GB
* Latest driver, latest bios
* Jvm arg -Dprism.order = d3d

This problem did not occur in the case of changing the startup options the next.

* Jvm arg -Dprism.order = sw
* Jvm arg -Dprism.order = j2d


This problem occurs in that you perform in a particular environment the following code.
I can play without problems in IE or Chrome, etc. in the same environment.

This problem occurs because playing time is longer,
It seems to be related to the playback time of the video.

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.layout.StackPane;
import javafx.scene.web.WebView;
import javafx.stage.Stage;


public class HTML5VideoTest extends Application{


@Override
public void start(Stage stage) throws Exception {

StackPane pane = new StackPane();

WebView browser = new WebView();
browser.getEngine().load("http://www.youtube.com/watch?v=tISgtgIRTZw");

pane.getChildren().add(browser);
Scene scene = new Scene(pane);
stage.setScene(scene);
stage.show();
}

public static void main(String[] args) {
HTML5VideoTest.launch(args);
}

}