Hi humbug,
Took me longer to find the time to do this than I had planned but it is all done now. At first glance, the lag and problem with audio/visual sync on all media player types seems to be gone. Online video's begin straight away, as opposed to stuttering into it, as they did before. So it seems like it has worked, or at least to some effect.
I am yet to try it out with Skype or any gaming, but I'm hopeful.
I do have a quick question, is there anything I should do in the CCC to improve the standard of things? i.e turning on (or off) things like triple buffering, anti-aliasing, vertical refresh etc.
Thanks again for your help, it seems like it's working