Animated gif within a WPF MediaElement stops animating after a few frames

I need to display some media in a WPF project. The media could be a jpeg, a gif, a png, a bmp or a wmv movie. So I'm hoping to use a MediaElement to do the diplaying. The problem is I can't get an animated gif to work properly.

I've seen a load of questions on here discussing how to display animated gifs within WPF applications, specifically:

1) Embed a windows forms Picture box within the app, which works ok, but the picture box doesn't scale properly when hosted within a ViewBox, so I can't use that

2) Create a custom GifImage which inherits from Image and do the animation myself. This works ok, but it means I need to worry about what type of media I am displaying, instead of just asking the element to deal with it (though I guess I could customise the object even further if I wanted to so it knew how to deal with all sorts of media). Also I think that some animated gifs only store the bit that has changed in each frame, so displaying the frame doesn't work properly - this one for instance: http://www.modernathlete.co.za/layout/banners/PEDI_Relax_469x60.gif)

3) Use a MediaElement and set up a trigger with a storyboard to loop the gif infinitely.

The 3rd method is the one I'm trying to get working as it (ostensibly...) seems like the easiest method. However, whatever I do, I can't seem to get the animated gif to loop - in fact, it seems to get stuck after 3 frames. The code is below:

<Window x:Class="WpfApplication4.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://sc开发者_如何学Gohemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:WpfApplication4"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <MediaElement Name="yourMediaElement">
            <MediaElement.Triggers>
                <EventTrigger RoutedEvent="MediaElement.Loaded">
                     <EventTrigger.Actions>
                         <BeginStoryboard>
                             <Storyboard>
                                 <MediaTimeline Source="http://www.modernathlete.co.za/layout/banners/PEDI_Relax_469x60.gif"
                             Storyboard.TargetName="yourMediaElement"  
                             RepeatBehavior="Forever" />
                             </Storyboard>
                         </BeginStoryboard>
                     </EventTrigger.Actions>
                 </EventTrigger>
             </MediaElement.Triggers>
         </MediaElement>
     </Grid>
 </Window>

I've tried the above with different animated gifs (these two: http://www.modernathlete.co.za/layout/banners/PEDI_Relax_469x60.gif and http://www.gifanimations.com/GA/image/animations/aliens/alien-01.gif), referencing them both directly from the internet, and locally (having downloaded and linked to them in a direct path to the file on the disk), but in all cases, after a few frames, the gif stops animating.

Am I doing something wrong here?

Have you tried the MediaElement replacement from the WPF MediaKit? That may work better for your needs.