05-18-2014, 01:44 PM
Ron is correct. It's cavitation from the boat. Most boats cause this and very few can be fixed by changing the placement. You can go to a stronger aftermarket transducer to fix the problem. Google Airmar P66 for the most commonly used transducer to fix the problem. It will have to be compatible with your unit as they make them with a myriad of connectors.
[signature]
[signature]