Audio and video gradually go out of sync

[Nick Payne]

I've been downloading the daily highlight packages from the BBC coverage 
of the World Snooker Championships 
(http://www.bbc.co.uk/iplayer/episodes/b00b436n). The first two episodes 
play without any problem, but the audio and video on the Day 3 program 
gradually get out of sync as the program progresses - they're in sync at 
the start, but by the end of the 50 minutes of the program, the audio is 
about half a dozen seconds in advance of the video. Has anyone else 
downloaded the day 3 highlights - if so, did the video and audio stay in 
sync? At the moment I don't know whether this is a problem with the GiP 
processing at my end or with the download from the BBC. Using GiP 2.94 
on Windows.

Nick