Just got a new Seac Screen dive computer (first computer I have purchased), and right out of the box it reads 1 foot while on the surface. Tested it in the pool (only 6 feet deep) and it consistently reads 1 foot too deep. I would expect some minor amount of tolerance underwater, but an error on the surface doesn't seem right. Is this error normal and within tolerance (and I'm just being OCD), or should I trying resetting, removing battery or replacement?