Eagle 320 signal going haywire?

Took the boat out Saturday am for the trolling. HAve an Eagle 320 on both front and back. After trolling for about 20 minutes the finder started losing the bottom signal and the image got soft. screen showed vertical lines. Voltage signal remained at 14 when trolling and waster temp held solid. Would show 130 feet in 7 feet of water then stop tracking. Transducer is clean. Unit works fine when I move it up front. Worked fine last week and the week before. THe ducer is only 1 year old. Any sugggestions? The only thing that has come to mind is I ran the GPS cords through the same hole as the finder cords to the console. Only thing I can think that was different is I had the GPS on this week and not last week. Electrical interference?

If your Eagle 320 worked fine on the front transducer, it is the other transducer that is your problem. Age of the transducer means nothing !!! Lots of problems with transducers !!! Good luck!

With the info provided I too am going to say ducer. When it is going haywire actually reach down in the water and feel the bottom of the ducer. If working you will feel a slight tapping. The tap can be different frequencies but it should be constant for some time. -Mark