IGMP Not Working - Errno(48)

[nish-na]

Hello,

I have been trying to set the proper firewall rules on my LAN and IOTS VLAN so Sonos on my IoT VLAN subnet could be controlled without switching my Wifi to IOTS VLAN. What do I need to do to make sure IGMP's working properly? I think that would fix my Sonos issue.

I also have Avahi and IGMP turned on. Upstream is my IOTS, where Sonos equipment is, and downstream is my Guest VLAN and LAN.

On my LAN and IOTS VLAN, I've opened the UDP and TCP ports Sonos lists here, but there's no activity on them:
https://support.sonos.com/en-us/article/configure-your-firewall-to-work-with-sonos

Under Status>System Logs>System>Routing, I see the following log entries:
can't join group 224.0.0.22 on interface mvneta1; Errno(48): Address already in use
can't join group 224.0.0.2 on interface mvneta1; Errno(48): Address already in use

Under Diagnostics>States, I see the following IGMP states, notably nothing from IOTS VLAN:

Under Services>IGMP Proxy, here's my upstream/downstream and IP addresses:

IOTS VLAN

LAN

[nish-na]

Has anyone else had any experience with this?