I have Infuse pro. I am wondering if Dolby digital plus (eac3) is supported or known issue with it for passthrough? I only get stereo when playing files with 5.1 eac3 (my receiver does support it). With Apple native player via homesharing it will decode eac3 and pass 5.1 PCM, so I know the track is fine. On apple tv i have surround to auto, reduce loud sounds off, and passthrough enabled in Infuse. DTS and DD passthrough all work fine. The file is h.264 in either mp4 or mkv.