Wow, I would check with the police and/or fire department and have them look at the installation of the car seat and have them look at your baby all hooked up in the car seat.
We thought the shoulder straps should always be slightly above the shoulders, too, but when we went to a car seat safety thing with a video and all, they even gave us a free car seat, the fire department volunteers were on hand to help install the seats into our vehicle and then to check that the baby was latched in appropriately. They made us move the straps to below shoulder level and said they should never be above shoulder level.
Have yours checked by officials because you'll get a different story from people who are told differently by everyone else.
By the way, police and fire departments check car seat installations for free - they care about the safety of infants and children in the vehicles.
at 8:33 PM on Jun. 27, 2009