Hdmi audio drops out - goes mute at random times

Just bought a unit during Oct 2011. It took about an hour for it to do all the firmware updates across a high bandwidth broadband connection. Firmware update server must be super S L O W. Now I think I have the latest updates but I hear the audio randomly go mute when playing VOB files. Same TV and cable that works perfectly for a competitor’s media player. I can ignore other defects or lack of features but mute audio is not one of them. I’m hoping there is a firmware fix or I will take this back to the store.

Either post the mediainfo of the files to check if there’s somthing wrong with them (Something outside what the WDTV plays) or r oll back the firmware to experiment.