My experience in the past with trying to do broadcast commands with the UDP symbol is it doesn't work.? But it has been a while since I tried so that may have changed. I've only gotten it to work with pointing it to a specific IP address and doing a one to one communication to another device.
Multicast is a whole other story.? When you send a multicast address, the MAC address is also changes. It is that special MAC address that allow the multicast packet to be routed to the right ports.? Now I am not sure if it is the switch that changes the MAC or if the sending device device that does that MAC address translation. But according to , it looks like it is the sending device that generates the multicast MAC address.? If that is the case, I highly doubt the Crestron UDP module will handle that MAC conversion -- instead, it will probably just send out the MAC address of your processor.