[CentOS] k3b doesn't burn video disk

I create DVDs from camcorder output.  In the past I've always just dragged the 
AUDIO_TS and VIDEO_TS folders into k3b and the disk has burned successfully.  
On this new box I tried to do the same, but k3b says that it 'Found invalid 
entry in the VIDEO_TS folder (AUDIO_TS).  That seems to be utter nonsense, if 
it means that AUDIO_TS is inside the folder VIDEO_TS.  If it doesn't, 
AUDIO_TS is empty, as it always is for these videos.  It has never been a 
problem in the past.  Does anyone know the cause?  Thanks

Anne