Error invalid-bitrate in AMS5

Hello everyone,

When I make multi-bitrate from a video and stream them live on Flash Media Server my users can play this videos in "http live streaming" but   sometimes when the second or the third user wants to play this live streams at the same time, previous user becomes DISCONNECTED and gets the Error invalid-bitrate

My codes are as follows

ffmpeg -re -ss 00:30:00 -i j:\movie\need4speed.mp4

-preset ultrafast -threads 1 -vcodec libx264 -b:v 2048k -r 24 -g 24 -keyint_min 4 -x264opts "keyint=4:min-keyint=48:no-scenecut" -s 1710*720 -acodec libmp3lame -b:a 16k -ac 1 -ar 44100 -f flv rtmp://12.11.1.2/livepkgr/need4speed720p?adbe-live-event=liveevent

-preset ultrafast -threads 1 -vcodec libx264 -b:v 1024k -r 24 -g 24 -keyint_min 4 -x264opts "keyint=4:min-keyint=48:no-scenecut" -s 1140*480 -acodec libmp3lame -b:a 16k -ac 1 -ar 44100 -f flv rtmp://12.11.1.2/livepkgr/need4speed480p?adbe-live-event=liveevent

-preset ultrafast -threads 1 -vcodec libx264 -b:v 600k -r 24 -g 24 -keyint_min 4 -x264opts "keyint=4:min-keyint=48:no-scenecut" -s 856*360 -acodec libmp3lame -b:a 16k -ac 1 -ar 44100 -f flv rtmp://12.11.1.2/livepkgr/need4speed360p?adbe-live-event=liveevent

-preset ultrafast -threads 1 -vcodec libx264 -b:v 350k -r 24 -g 24 -keyint_min 4 -x264opts "keyint=4:min-keyint=48:no-scenecut" -s 570*240 -acodec libmp3lame -b:a 16k -ac 1 -ar 44100 -f flv rtmp://12.11.1.2/livepkgr/need4speed240p?adbe-live-event=liveevent

-preset ultrafast -threads 1 -vcodec libx264 -b:v 128k -r 24 -g 24 -keyint_min 4 -x264opts "keyint=4:min-keyint=48:no-scenecut" -s 342*144 -acodec libmp3lame -b:a 16k -ac 1 -ar 44100 -f flv rtmp://12.11.1.2/livepkgr/need4speed144p?adbe-live-event=liveevent

Please advise me to fix this problem in AMS 5 Extended edition.

Any help will be appreciated