Users not able to watch videos greater than 10 mins

[khav]

My site does video streaming and users are not able to play videos greater
than 10 mins.After 10-11 mins flowplayer stop playing the video but i don't
get any error either by php/nginx/flowplayer
Is there anything wrong with my fastcgi buffers

      fastcgi_pass   unix:/tmp/php5-fpm.sock;
        fastcgi_index  index.php;
        fastcgi_param  SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include        fastcgi_params;
	    fastcgi_connect_timeout 60;
        fastcgi_send_timeout 300;
        fastcgi_read_timeout 300;
        fastcgi_buffer_size 128k;
        fastcgi_buffers 256 16k;
        fastcgi_busy_buffers_size 256k;
		fastcgi_max_temp_file_size 0;

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,255549,255549#msg-255549