spews annoying warning messages. But, we can't simply remove the release calls of these jack instances because they have to be freed when the codec is re-configured. Now, a new flag, bus->shutdown is introduced to indicate that the bus is really being unloaded, i.e. the objects managed by the device manager will be automatically deleted. We release these objects only when this flag isn't set. Signed-off-by: Takashi Iwai ª»%U“