SOLVED Setting Multicasting Max Bitrate Via webinterface
In some cases multicast speed could be very poor. Especially when your for server is linked to your switch with a 1Gb/s link and your clients are on 100Mb/s links.
One workaround is to force the --max-bitrate option of udp-sender to a value around “80m” (best compromise in my case). Actually it must be done by editing service/common/lib/MulticastTask.class.php manually