what pulseaudio sinks/devices do you have?
there are a number of things you can do to improve boot times. nscan probably won't effect it much because it's one of the last things that loads. It will effect responsiveness after boot though if you have a massive library. There are a bunch of threads that discuss disabling it both here and on the forums.openice.org forum.
One of the easiest things to do is to format your drive ext4 during setup. Also consider upgrading to 9.10 or 10.04 as both boot much faster than 9.04 (caution, there are some manual changes to have to tweak to get it to work. there's a couple threads on the upgrade procedure as well).
hope that helps ;).