I have encoded some content in 12 different bit-rates in mp4 format with 2 sec chunks ranging to HD to SD content with Max bitrate as 6Mbps to lowest as 200kbps.

When i stream the content with silver-light player, the bit-rate fluctuates too much and it never reaches the highest bit-rate and maximum it has reached till 2 Mbps. I a not finding any network issue as the effective bandwidth of the network is more than 8Mbps so ideally anyhow it should play the highest bitrate of 6Mbps.

even if its playing with 2Mbps, its not stable at all and fluctuates randomly and very oftent from 600Kbps to 2Mbps.

Is there any configuration which can fix it or any hints which can me resolve this issue?