With 15.5 SP4, we have a step toward supporting multicast more fully. However, there are things that are desperately lacking that would make management of phones much easier and eliminate most of my custom templates. Add ability to configure a BLF in 3CX to multicast paging. As in, selecting "multicast" from the dropdown gives you three fields Label IP Address Port Add ability to configure multiple multicast listening groups. Make a dropdown with checkboxes that show all available groups.