When I create an multi chaptered AVCHD using aultiAVCHD, or a single file for that matter, all appears to go well and the structure appears intact except the Audio is weak and it is made up mostly of "white noise" which is 75% of the audio. The log file shows transcoding some failure under Haali, Avisynth and ffdshow, which I've uninstalled and reinstalled (64bit if avail) a couple times and authored the folder again using multiAVCHD making sure the match the bitrate and checked one of the stream files and the same white noise exists.

The original mp4 files are PCM and play fine. The multiAVCHD Authored stream files are AC3 and playable but are they 75% missing and replaced with noise.

I know I need to give more info but I'm just not sure what?