I discovered that you couldn't mux a Video File with a LPCM audio file using TmpgEnc Plus or other software iv'e tried.
So i decided to use Tmpg Author 1.6 to do it.
This is how:
Click on create a new project, add your video m2v Video file or vob.
In the video section above you'll see the file you just added.
Then you add your LPCM file in the audio part below (which will overide whatever audio is with your video above, if there is any).
Then you bypass the menu precedure by selecting no menu, then output the file to a your selected folder. If you want, you can edit the video in the chapter cut section before output begins. Because you are outputing one Video or Vob only, it happens very quickly....like normal multiplex in Tmpg-Enc Plus or whatever else you use to Mux and De-Mux.
Find the folder with the finished Vob and you can do what ever you want with it...render to S-vcd, vcd or keep it as the Vob to use later when producing a DVD.

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