I was debugging a problem with stuttering video and noticed something that I have not been able to figure out. The stream buffer length is set to 8 secs and when there is enough bandwidth, the buffer fills up and keeps filling up way past the 8 secs. I've seen 24, 30 and if I pause the video, it just keeps going.

The files are hosted on Akami with FMS 3.5

Is this normal, is there a setting some where that is effectively turning the stream into a progressive video if it can.