XVid to DVD but no sound

I have encoded an Xvid to Mpeg2 using TMpegEnc. then into DVD format using ‘Ulead DVD Movie Factory 2’.

When I play the individual VOBS as media files in RealOne player I have sound, but when I play the whole lot as a DVD I have no sound.

I’ve tried several different software DVD players and none of them produce sound. When i burn it to disk, I get the same result in my DVD player.

Any ideas whats going wrong? Thanks for any help.