GS108E - Missing IGMP Snooping Option

Hi,

   I have a GS108EV2 switch, and i need to use it to dispatch Multicast data to my ISP TV Box.

   On my Prosafe Plus Utility, on the multicast tab, here are my options :

   But on the documentation and for an counterpart model (GS105EV2), i have an extra option "IGMP Snooping static router port", which is required in order multicast flow to work.

   Why i don't have this option ?

   My switch has the latest version (1.00.12) and the Prosafe Plus Utility,also (2.3.19)

Thanks for your help.