Video's not showing after laptop upgrade/change

G'day,
I recently upgraded my laptop and for some reason, the Videos will no longer show. All I get is a black screen in the video preview and master out windows, however the audio of the video file plays fine.
All the audio functions are also flawless..
The only aspect that I can think would be 'the' issue, is that my new laptop only has 8Gb Ram, whereas my old one had 16.
All other aspects of the new laptop are better than the previous...
Current laptop specs : i7 6700HQ 2.5ghz, 8GB DDR4 2133, Nvidia 940MX 2GB DDR3, 2 X 1TB SSD drives

I am upgrading the ram to 16gb when it arrives from the store this week. Hopefully that is the issue. If not, Any help would be appreciated.

Thanks
B3RN