I have two Nexus 9k's in a VPC receiving multicast data. Both switches have non-orphaned ports receiving the multicast traffic.
The problem is that the VPC peer-link is holding onto the IGMP snooping group when no other devices are are joined.
This is leading to a flood of non-requested multicast data into my system.
All IGMP snooping groups that only have the peer-link as a member show Last Reporter: None.