Impulse only playing once?

So whenever I use an Impulse source, instantiating a new one or using one that's in the scene, it only plays once, what might be causing this?

EDIT: So it looks like I can get it to play multiple times, but there seems to be a delay if i spawn multiple too quickly, is there a "cooldown" requirement somewhere?

EDIT: So it looks like this only really happens with the Legacy profile on the Impulse Source.