@electronic_eel I see! You could achieve this by creating separate virtual devices and running multiple bark stream processes using separate multicast groups for each speaker. You'd lose the benefit of multicast, since you'd essentially be unicasting to each speaker (but in a roundabout way via multicast), but the actual synchronisation runs according to CLOCK_BOOTTIME on the source host, so provided all stream sources are running on the same machine the sync would work.
@hailey ah, cool!
I don't care about network bandwidth as all sinks have direct ethernet cables to one switch. So unicast or multicast doesn't matter for my application.
I think I will give bark a try soon.