Hello, I got a video from a concert (is on DVD), but also I got a FM full broadcast of it, which sounds better than the video audio. What software can I use for sync the video audio with the FM recording???. Is there a guide somewhere??.

Thanks,

There is no easy one click way to do this. You first need to demux the A/V from the DVD. Next you need to convert the audio to wav (using HeadAC3he or other tool). Then you need to place both audio files into an audio app like Cool Edit, Audacity, etc, and make the FM broadcast sync to the original. This can be done by changing the speed of the FM, cutting very small pieces, etc.... Then recompress the audio to the same format/bitrate as the original DVD (AC3, MP2, PCM Wav, etc), then reauthor/remux the new audio with the original video.

Ok, Thanks, so with some software that demux/mux and audio editor and converter, can I do it???, Also, there is a way to keep menus from original DVD???.

Thanks again,

You can keep the original menus. Reduced compatibility can happen if you try to retain the original menu/VOB structure. It is best if you reauthor to retain assured DVD compliance.
The problem you will most likely run into is the speed of the audio for both sources. Most analog devices will record at slightly different speeds, which will cause the new audio to drift out of sync. This is why you will need to edit the FM audio in a multitrack wav editor to make it match the original audio. I can't tell you which is the best way to make the FM audio match, because for me, the amount of "drift" will require a different technique for different situations.