New eac3to GUI: HD-DVD/Blu-Ray Stream Extractor - Doom9's Forum (
http://forum.doom9.org/showthread.php?t=141829)
I didn't read all this because the thread is big and spans multiple years, and I have no Blu-ray drive so it does little for me, but it sure seems people have had success ripping Blu-ray audio with this. I hope it's useful for you and good luck in your endeavors!