I've read a lot that you guys have posted about getting feedback on your units but I still can't figure out my problem. I've got a 997 at the steering wheel and a 957 up front.....if I use the 83khz transducer I get blue lines in my graphs....the only thing they have in common is that they come off the same battery...one is wired on the left side of the boat and one on the right.....any thoughts on what I might could check????