I've had the XVT3D554SV for more than a couple of years now. I don't really use my PS3 much, but I was playing a few rounds of Battlefield 3 the other night. I normally don't use game mode, but I figured why not try it. In game mode, the screen will flicker once every 2-3 minutes, sometimes more. And when i say flicker, I mean the screen goes blank for a couple of seconds. I have tried turning of smoothmotion and then enabling game mode, but that was no different.
My tv stays connected to the wi-fi, so I'm assuming it's the latest firmware, but I'd have to check the version to make sure. Any ideas on what else it could me?