Dell 2335dn scan size problem

When I try to scan using the auto loader tray on top, the scanned image is mashed. The settings that I'm using is resolution: 300 dpi, scan color: color, scan format: jpeg, duplex: off, scan size: letter. I have uploaded an example. If I scan using the glass, it works perfectly. But there are occasions where I need to scan multiple pages & using the glass just will not work. There is only one setting that works if I scan using the auto loader tray on top and that is if I choose the scan color: gray. Every other option, color, 256 color & mono do not work and I end up with the mashed scan. I need to be able to scan images with color. What is the problem?