Recently purchased a Nikon D3300. Works great except that the flash is causing a shadow along the top of the frame. I swapped out lenses, played with modes, played with the flash and photographed indoor and outdoor and narrowed it down to the flash. I've seen posts where there's a shadow along the bottom because of a long lens and I've seen posts with pure black blocks across the top because of shutter speed, but I haven't come across this. Any help is appreciated.