Youtube FLV has no NetStream?

Hey
I’m currently testing whether it’s possible to create a lightweight soundmixer/loopmachine web application.

I’ve successfully connected flash to call a php script that fetches and return the flv used by the youtube player to my application. However, when I try to play it I get this error:

Error #2044: Unhandled NetStatusEvent:. level=error, code=NetStream.Play.StreamNotFound

It plays just fine in vlc. How can it not have any NetStream and still be able to play in the youtube flash player?