I have an Eagle, Fish I.D. 128. Depth and fish finder. It's a portable model that runs off batteries or I use it with my trolling moter battery. This year it's getting "Stuck". At first it wouldn't come on at all and when it did it stuck on 1.5 ft. It would work right for a little bit and stick again at 9.0 ft or whatever. I checked the plugs and wires, didn't see any problems. Any Help would be appreciated..