Not sure what cam and whether you mean in the config in the cam or that in BI.
In the cam try:
640x480, variable bitrate, Medium quality, 15 for frame rate, bitrate 512, H.264, I Frame 15
Match the FPS, IFrame, and encoding to that of the main stream. You can adjust higher if you want a better quality substream.
In BI for the second stream config try:
/Streaming/channels/102