i have a 997 at steering wheel and a 787 up front,both are color graphs. i am getting alot better detail on the 787. i like to mark fish on my 997 before we fish, but we are not finding any fish on the 997. then we drop the trolling motor and go thru the same area and the 787 shows all kinds of fish on the screen. has anybody else had this problem. i have the 997 setup the way it is supposed to be but it is not working right.