I have a dvd that I have simply dropped the .VOB file into vegas 11.
DVD Plays fine with no blips or jumps.
No visible blips or jumps when previewed in vegas.

However: When I render the file back out there is always a "blip" in sound or video or a bit of wobbly frame somewhere on the clip. (not always in the same place).
Its usually only a quick blip no more than half to one second and only usually once during the 5m clip.

I render out as .mpg PAL DV 4.3 and have tried progressive and non progressive scan. (I need to use the file with progressive scan eventually).
I have also tried constant bit rate and variable bit rates.
Also tried to render as .avi PALDV with the same problem.

Anyone got any ideas?