HLS multibitrate video switching on 3.0 vs Roku2

I have a live, HLS channel that has two bitrates, one is 564, the other 1064. I am setting the bitrate to the higher rate to start streaming, based on the recommendation to not set the bitrate to 0 for faster streaming start.

On the Roku 3.0 it seems to start streaming at the lower bitrate and stay there, on the Roku2 it goes right to the high quality video, usually, or eventually switches to the higher bitrate.

Anyone have a suggestion on settings to optimize for both platforms?

- Joel