I actually have no idea how long this problem's been around on my computer as I don't often watch video clips on it, but the other day I was trying to view a common wmv file and it would only play out the sound but not the image/graphic.
I tried the latest version of WMV then moved onto VLC, Media Player Classic, and GOM Player but the same problem persisted. I then found that the same problem also happens to other common video formats - avi, mpg etc.
The videos I've been trying to view work perfectly with image and sound on other PCs with same players.
I can view Youtube videos.
Windows XP SP3, nVidia