Sound shift after encoding avi to mpeg2

[Lisandrea]

Hey you encoding specialist!
I have tried to transform avi files of about 700 MB into DVD-Pal complient MPEG2 files with Ulead Movie Maker or TMPgenc. In the resulting file everything seems to be ok during playback till the middle of the file. However, then a shift between video and audio happens, which means, that audio comes somewhat after video.
What can I do? Has it something to do with frame rates?
Every bit of help is highly appreciated!
Lisandrea

[Lisandrea]

Here again Lisandrea,
I found out what was wrong. The audio shift is just caused by corrupted frames. However, Ashampoo Movie Shrink and Burn had no problems with the files and produced fine SVCDs.
Thanks to all readers!
Lisandrea