Multicast enhancement
FortiOS can translate multicast traffic into unicast traffic to send to clients, maintaining its own multicast client through IGMP snooping. You can configure this in the CLI:
config wireless-controller vap
edit example_wlan
set multicast-enhance enable
set me-disable-thresh 32
end
If the number of clients on the SSID is larger than me-disable-thresh, multicast enhancement is disabled.