I have a three knob shower, hot, cold, and a center diverter knob. Everything works fine except when I divert the flow to the shower head, water continues to POUR out of the faucet. I wouldn't really care if it were a small trickle, but it really seems like a huge waste pouring out like it does. I have recently changed all of the stems, seats, gaskets, handles, etc. but no noticeable difference. Help!