So I have confirmed that I can do AC3 Pass through on the Iphone 5 with hdmi to a compatible receiver. To do that I stream a mp4 video with an AC3 track and get the full surround sound on the stereo over wifi. The issue I now have is encoding a video file that can reside on the phone yet still output an AC3 audio track. Itunes will not let you copy a ac3 only file over to the phone as it is not compatible with out an external receiver. What I read online was you needed two audio tracks, the first ACC and the second your full ac3 file. I have created that file with these properties and can not get it to work. When playing the file on the phone with no hdmi I hear the ACC audio track. When plugged into hdmi to the receiver I get no audio. Any suggestions? Interesting note the h264 decoder doesn't seem to have any issue decoding upward of 50mbit video streams!