I'm bumping this thread because I found a work around for this that I haven't read on any help forums yet. And yes, I tried the IPv6 thing, which actually made things worse, and everything else.
The problem I had was playing itunes through remote speakers after my computer had just woken up; it would through this error everytime until I restarted iTunes. If you use the remote app for the iPhone this can be annoying to need to do everytime. However, if you set the speakers to "Computer" then immediately set it back to your remote speakers, then an iTunes restart isn't necessary. It's still annoying that this needs to be done, and wasn't necessary for me in iTunes 8.0, but at least you don't need to go restart iTunes every time.