Janet,
Are you talking about the FD-UR blades? These blades have a little marking on one end. On the label it tells you if it is the top or the bottom of the blade. Numbers 1, 3, 5 means the top. The numbers 7, 9 it is the bottom. Someone in the factory made a mistake.
If you get splinters on the bottom, you might not have enough tension, or you might use regular plywood. This has a very soft core and splinters easy. That is why most use the Baltic Birch.
If you don't have enough speed, you have a tendency of pushing too hard into the blade, you will lose control over the blade. Instead of cutting the wood, the blade starts grabbing it.
FD Mike