It does sound like multicast flooding in theory but without knowing the setup of the SH2 its hard to know. Surely fundamentally though the SH2 has an internal setup intelligent enough not to flood the network with multicast packets when IPTV is switched on at the ISP. Sure if you were using a 3rd party router not setup for IPTV at all its possible but I really cant imagine the SH2 is that dumb.
It does interest me how it is setup on the SH2, all the ports will work for Multicast tele along with its WIFI, but it must have some mitigating setup to avoid flooding all the devices connected via Ethernet or WIFI that do not want those packets. Having to set that up on a 3rd party router can yield varied results, in fact I find it most easiest to just use a single port and send all the Multicast there, so the SH2 is cleverer than me, I hope.
Potentially the addition of the boxes is causing some additional WIFI load which is enough to slow the Nest's slightly, I havent spotted if you said if the EETV's are connected via WIFI but I assume one is?
As for some stats, with my EETV in standby the current throughput to its interface is more or less constantly around 75 kbps, very small amount, of course if I power on the box that will rise to Megabits depending on the channel.
As for my IGMP proxy:
Box in Standby checking 3 times a few seconds apart
Group Origin In Out Pkts Bytes Wrong
234.81.x.x 109.159.x.x eth0 eth4 22348347 228.49MB 0Group Origin In Out Pkts Bytes Wrong
234.81.x.x 109.159.x.x eth0 eth4 22348384 228.54MB 0Group Origin In Out Pkts Bytes Wrong
234.81.x.x 109.159.x.x eth0 eth4 22348444 228.61MB 0
So there is a steady tick over but nothing significant, nothing I think that would flood anything
Box streaming Sky Sports Main Event checking 3 times a few seconds apart
Group Origin In Out Pkts Bytes Wrong
234.81.x.x 109.159.x.x eth0 eth4 22350315 231.03MB 0
234.81.x.x 109.159.x.x eth0 eth4 38547 49.85MB 0Group Origin In Out Pkts Bytes Wrong
234.81.x.x 109.159.x.x eth0 eth4 22350351 231.03MB 0
234.81.x.x 109.159.x.x eth0 eth4 43673 56.48MB 0Group Origin In Out Pkts Bytes Wrong
234.81.x.x 109.159.x.x eth0 eth4 22350380 231.12MB 0
234.81.x.x 109.159.x.x eth0 eth4 47815 61.83MB 0
So when a channel is streamed a new connection is opened up which is shown by the second IP which a much quicker rate of travel, as you can see the first line is still there at the same as it was in standby increasing in the same slow fashion, but the second line now present, is moving at a rate reflecting the channel traffic. Recording two channels at once and there would be a 3rd line there also.
What I am drawing from this is that when the boxes are in Standby, not alot is happening at all and I would be very surprised if any flooding took place, especially on the SH2 which should have built in mitigation for that anyway. In my case eth0 is connect to my ONT and eth4 is a dedicated port for my IPTV and my router is setup just to pick up multicast from eth0 and send it to eth4 where the only device connected is the EETV Box Pro. I can stick any switch on eth4 and connect multiple TV Boxes.
I dont think its your new EETV mate but happy for the above to be interpreted differently.
Edit: OMG the formatting is not ideal, sorry for that, the headings arent lining up as bring it over from putty is screwing it up, even if I use the code block.