12.04 update breaks video

[rikona]

On Fri, 1 May 2015 14:02:40 +0200
Liam Proven <lproven at gmail.com> wrote:

> On 1 May 2015 at 07:29, rikona <rikona at sonic.net> wrote:
> > ust updated 12.04 and video is broken. Neither VLC, Movie Player, or
> > Dragon player will show the video part of MP4, avi, or wmv files.
> > Dozens of MP4s that used to play just fine are all broken. Trying to
> > play these in Ffox gives "file is corrupted". A 14.04 box, recently
> > updated, plays MP4s just fine. The audio part seems to be fine -
> > just a black screen instead of video. . How can I find out what
> > happened and fix it?
> >
> > All suggestions much appreciated,
> 
> What graphics card? What driver for it? 

AMD A4-5300 APU with Radeon(tm) HD Graphics × 2

driver: ESA: DVST

FGLRX 3D-accelerated proprietary graphics driver for ATI cards.
--- activated but not currently in use