I'm going to tell you up front that I probably can't help, but I'll ask a bunch of questions, so maybe I can get you sent in the right direction. What software are you serving the videos from the computer? When you say it loses its connection, what do you mean? Do you mean the Wifi network connection is gone? Also, did you contact Samsung over there in the UK, and was it they who set you up with a tech call?
When I pauze a movie that I stream via Wifi from my PC or NAS, the TV loses it's connection with these sources when I un-pauze. This happens when the pauze is more than 3 minutes or so. How can I fix this?
I have installed the most recent firmware. The Tech service has replaced the wifi module and a plant reset. Still no solution.