flash player freezes then plays, then freezes, then plays!!

I have an issue when I am trying to view video content in any browser. The video will play for around 10 seconds then freezes for a couple of seconds. The video then plays in fast forward while it catches up and then plays for a further 10 seconds or so and then the same happens. This happens continuely while the content is being played. The audio seems unaffected.

I have turned hardware acceleration off but the problem still occurs.

Does anyone know how I can resolve this?

Thanks.