To show this without a wifi connection since wifi connections are problematic. There are long discussions about this with some finding cures with network settings and more.
I don't expect a fix from Samsung since your network is your network.
My Samsung UN40C6500 LED HDTV (4 weeks old) intermittently gets a blank screen for 1-2 secs. There is also a buzzing sound when it happens.
Attached to the TV: DISH Network VIP722K DVR, Samsung Blu Ray DVD BD-C5500C, Panasonic Sound Bar SC-HTB500PPK. I have the LINKSTICK connected to the TV.
I recorded the problem and the video is in Youtube. Problem happens at 17 seconds and 40 seconds into the video.