i have a bow mounted 998 with the transducer mounted on the trolling motor.
i added a 1.5 feet to the factory setting per instructions to get the correct water depth reading. i have noticed the last few fishing trips that i get a 2.1 reading an awful lot even though the sonar picture in 2d clearly shows that i am in 5 feet or more. so much so that when i look for a depth reading and the number shows 2.1 feet i automatically look at the picture to see the correct reading. i have also witnessed it shows 2.1, then correct itself to lest say 5.8 then 6.2, then maybe go back to 2.1 when the bottom is pretty flat.

whats up with that?