TV Issue

[gettysburgfreak]

Bought at 60" Sharp Aquos at the end of September from Best Buy. Things were great, had it for a week before leaving for Italy for 3 weeks. Get home, watch it for a few weeks and then out of no where the TV starts to have a white flash appear at the top of the screen. It is completely random and doesn't do it consistently. I tried calling Sharp, they had me do some factory reset stuff, thought the problem was fixed but my wife said she saw the tv do it a few more times last night. Called Sharp again today and they said they would search around and try and find someone in my area come out to look at it. Im keeping my fingers crossed but pretty pissed a TV I don't even have paid off yet is effed up.

My question is this: Has anyone experienced this before? I did switch from Comcast to the Comcast X1 but my other two tvs don't have this issue. Has anyone had luck with Best Buy exchanging a TV even though their return policy is 15 days? Any ideas would be great.