My tub faucet was leaking so I replaced the valves in the two handles for hot and cold. Since changing the valves, I am getting much lower water pressure coming out. It is so low that when you turn either the cold or the hot on and then you turn the other one on, you notice no change in pressure at all. I made sure to match up the valve number on the bottom of the valve so I know I have to correct one. Any ideas??