Random "Flashing" on DVB-T2 in UK

[CyberSimian]

At the moment I have a single TBS 6284 quad-tuner card in my HTPC. It is a fresh install of Windows 7, with all maintenance applied. I am using version 1.0.0.3 of the TBS driver, and watching TV using Windows Media Center. The graphics card is an Nvidia 8400GS, and the drivers are version 301.42 (the most-recent WHQL-certified drivers).

DVB-T broadcasts are received satisfactorily; the problem is with the DVB-T2 broadcasts (there is one DVB-T2 MUX in the UK, currently carrying 5 high-definition channels). Randomly, the screen will briefly lighten (similar to the effect seen when a flashgun on a camera is discharged in the field of view of a TV camera). The time between flashes can be as short as one second, but can also be longer; it seems to vary randomly. I have checked all of the 5 HD channels, and they all exhibit this effect, although the severity of the effect does vary from day to day, and from channel to channel. So that you can get a better idea of the effect, I have recorded a brief sequence from the Olympic games, which you can download from my web site. It is circa 14 seconds long, and 11MB in size; there are around 5 flashes in this 14-second clip:

http://www.xenscape.com/anon/olympic_archery.wtv

Out of interest, I installed the latest version of the TBSviewer program. It is not as easy to set up as Media Center, but when I did get it going I was surprised to find that TBSviewer does not exhibit the flashing effect -- the high definition channels seem to be as good as they should be.

Any ideas as to the cause of the flashing? Something wrong with my setup, or a bug in the software?

-- from CyberSimian in the UK

[CyberSimian]

Some discussions on another forum indicated that the problem might be caused by the Nvidia drivers. I was using version 301.42 (WHQL certified), so I downloaded and installed version 304.79 (a beta version), and this seems to have fixed the problem. Panic over!

-- from CyberSimian in the UK