Flash/flex component Youtube like seekbar

I am developing a audio player in flex. I need a seekbar kind of like on youtube's video player. To implement the basic seek functionality the HSlider com开发者_JS百科ponent is enough. But I also want to show the stream progress on the seek bar. (youtube colors the already streamed part of the seekbar red). Is there a way I can achieve the same? I am also open to suggestions of a drag and drop audio player component with play/pause and seek functionality.

I would extend the HSlider component to include a percentage property for progress, then create a custom skin to draw that value within the track for the HSlider. Let me know if you need details on creating/using skins and whether you are using Flex 3 (halo) or Flex 4 (spark) components.