Unable to set Start/End time on DVD clip

O/S: Windows 7
Version: trunk 2.1r2434
Latest version of VLC.

Library -> Media -> Load CD/DVD
Loaded a Mamma Mia DVD.
This loaded 9 tracks and defaulted to the first one (the film).
In the track dropdown list each track showed the correct track length.
However in the dialog, the "End Point:" defaulted to 00:00:00.0 (this normally defaults to the end of track).
I was unable to change either the Start Point or End Point either by using the up/down arrows or typing in numbers. I was also unable to move the slider underneath the preview. Note however the clip played fine.

I switched to a different track and had the same problem there. However a third track worked fine.
Switching back to the first track still didn't work.
However switching through all the tracks and then going back to the first track then allowed me to set the Start and End point.