Media Not Playing eg Youtube, Itunes etc

Hello,

I purchased a new laptop about 6 weeks ago and I have been noticing a few issues with playing media. I have vista installed and whilst I see many solutions people have posted to vista issues is to uninstall and get Mac, I am not looking to change over from microsoft.

The problems began about 2 weeks into my new purchace and below outlines the issues I have come across to date:

- Youtube files do not play sound (picture quality is fine) and yes I have checked the volume controls on my laptop.
- Itunes does not play. When I hit the play button it just sits at 0:00
- Media Player Classic (which I installed) does not play sound and when I hit play, the first second or 2 of the video is jumpy, it then plays normally (without sound) for about 10 seconds before freezing on the frame while continuing to play. If I click the play bar to the 10 second mark it will then repeat the process (ie. the first second or 2 of the video is jumpy, it then plays normally (without sound) for about 10 seconds before freezing ).

Now something else strange happens. For some reason when I have Windows updates, following installation of the updates, the above problems magically disappear. However, after the first restart or shut down they return.

I would love to be able to resolve this issue. Can anyone help me please???

Cheers