Did you rip all of the audio tracks or just one? Typically, on BD, the main English audio is DTS, DTS-HD or Dolby-TrueHD; the descriptive audio, if any, as well as director's comments, if any, may be AC-3/5.1 or AC-3/2, though exceptions my occur. The Highest quality audio is usually the main English audio. You can always play the original BD and select through the various audio options when playing the main movie and make note of what is what. If in your rip, you only have one audio track, then you likely ripped the wrong one. I think you can also preview the audio tracks in the built-n player in DVDFab. Select each one in turn (turning all others off) and preview in the preview mode.