I had no time the past week to get on the phone and deal with this between my day job and home schooling my 4 kids and trying to keep up with the honey-do list. 😉  I finally called yesterday morning and continued debugging.   As I expected, my suspicions were confirmed and I was not losing my mind. The switch is behaving unexpectedly with IGMP snooping. It initially works when I relocate all the multicast receiver hardware onto the switch and I reboot my gateway router. It even makes it past the typical IGMP dead timer of 270 seconds. For unknown reasons at around the 7 minute mark, the receiver sends an IGMP leave report, even though the box is still tuned to the same video stream. At that point, the switch wipes all of the multicast forwarding and loses track of the router forwarding the source content to the group, even though the switch can still see IGMP reports from the router including the IGMP group in question coming across the uplink port.   The issue has been escalated to development to isolate and hopefully identify a firmware bug fix. I will update when I hear further information. ... View more