TAP bridge - checking multicast and broadcast

[thisisliam]

Hi all. I have a TAP bridge set up on two OWRT routers for two remote devices requiring multicast and broadcast traffic to communicate. Despite setting up a bridge that allows me to receive an IP address from the server, see devices on both ends and use the internet, something still isn't working. From what I can see, Broadcast traffic is traversing the tunnel but I think multicast is not. I have been using tcpdump to try and troubleshoot. Is there any specific tests or commands I can run to monitor multicast/broadcast specifically traversing on the tap bridge?