Have you installed any of the latest updates? I think they addressed this issue and it worked for most.
I have a HB MEGA Gen2 10 that after about a year sometimes freezes up and adds to 10-12 feet to the depth readout even tho the depths on the DI and 2d are correct. Mostly happens more often when I get around 10 foot of water. Comes and go. Last 5 monutes or so and then corrects itself. Few minutes later it happens again. Aggravating.
Have you installed any of the latest updates? I think they addressed this issue and it worked for most.
Also try setting max depth in sonar setup to just over the deepest depth of your lake. My home lake is deep, over 90' in the main lake channels, so I set mine to 120'.
"Alive without breath, as cold as death; never thirsty, ever drinking, all in mail never clinking."
Seems like the latest update fixed the depth issues I was having with my Helix 9 Mega DI/GPS.
Sent from my iPad using Crappie.com
Latest update fixed that issue with mine and it did it 3 or 4 times every outing