demuxing issue - IFO problem?

[Michael Coates]

hi, i recently created a 25 minute vob file from two other vob file - i used tmpgenc dvd author to join them together and it worked fine - now i find i need to change the audio from ac3 to wav so i used vobedit to demux only when i do this i get some serious problems, the video plays fine but media player says it's only 18 minutes long (the length of the first movie) while the audio is still 25 minutes long. i've demuxed lots but always get the same results. so i changed the audio to wav and re-muxed, only this time the picture is totally out of sync and speeds up a lot. basically it doesn't work!

i figured it could be a problem in the IFO file, perhaps it only picked up on the first movie when i joined the other vobs? hmm, not sure - anyway i guess what i'm asking is if anyone else has had this problem and whether or not ffmpegx might do a better job of demuxing the joined vob?

any help or advice would be greatly appreciated!
thank you for reading.
michael x

[Michael Coates]

ok, forgive me for posting this here, i just went to download it and realised it's a mac program not a pc - i will try and post this somewhere more relevant. sorry for wasting your time.