Ordered my 27" iMac Feb 6th. Received it today booted up yellow tinge on bottom of the screen, and a yellow line about 2.5-3 inches thick was visible down the screen on a white background. After a few min the yellow line went away now I have a blue line in a different location on a black background. These lines are not visible on every color only black and white. I have not contacted Apple yet. Could this be from the cold of the FEDEX truck in PA?