[vlc] Mpeg2 file stuck at first frame

[Ian Evans]

I've been using VLC under Ubuntu to grab snapshots from Mythtv
recordings that don't have any fan art. It's been working great,
however there are several recording that play fantastic under MythTV
but when I go to load the mpeg2 file with VLC, it just loads the first
frame and goes no further.

What would be causing this and what can I do to get past it?

Thanks.