I just thought about something like that... There should be a
possibility in headsetd or maybe the plugz, that would switch to a
fallback device, if the headset can't be connected (it's switched off or
whatever). The way it's working now - dropping the stream to /dev/null
or wherever is not a wanted behavior, when someone calls You on a softphone.


-- 
Cheers,
Michał Sawicz