You should not have to convert the audio to any specific type to use it with the WD. The WD handles many more codecs and containers than the Tivo. It just needs a clean start so it knows what it has. If you go back to the link I originally gave you, you will see that Dan S was able to use the VRD timeline to show the different audio segments in his recordings in different colors. By cutting away the initial commercials with the wrong audio, he was able to play the 5.1 audio from and HD without issue. I also use my WD TV for 5.1 surround sound but I have always used VRD and Quick Stream Fix to clean up the streams before I copy them to my NFS server for playback.