4 colorful circles on black screen—-HELP

The multicolored circles are the SONY boot " logos" (for lack of better term)I think Android has something like that also. Unfortunately the high cost of a product is no guarantee it cannot be defective or have a small glitch. I would guess if it's a new TV it tried to update its firmware and is stuck in a boot mode. If the TV wont turn off you may have to unplug it wait a good few minutes and plug it back in. The U-verse set-top box would not cause it to have multicolored dots. If the U-verse set-top box has issues you usually get red or gray X's, gears or 3 dots gray or white not multicolor. Also the TV would turn on and off and function as normal otherwise.