my unit is 2yrs old transducer is mounted on the trolling motor. it has been working fine till now, it works like it should for a little while then acts like it freezes up.it has a spilt screen on it, left side shows what they call sonar view, right side shows what they call real time sonar or (rts). say your setting in 10ft of water, both sides show 10ft, then it messes up ,left side will show 0.6ft depth, screen is black just like transducer is on bottom, right side will still be showing 10ft,it will stay like this for a while then go back to working right for a little bit then it will mess up again. does not matter if trolling motor is running or not. thanks for any ideas or help.