I have a 1 1/2 yr old Helix 7. Mounted in front of boat, transducer on transom, and transducer on trolling motor, also have a selector switch to pick the want I want to use. Last two times out, I am getting a low voltage message after running for awhile, also front transducer doesn't not accurately read depth. example, back trans reads 4 feet of water, front may read 1 or maybe 10 or maybe 4. Also I loose the bottom while moving anything thing faster than 10 mph. Have tried adjustments per install manual.

I know there is not a voltage issue