My bow unit is a Humminbird 788ci, and has been giving me problems with showing correct depth. It has been getting stuck on 0.6 ft most of the time. I was told a couple of things to try that didn't solve the problem. I tried restoring default settings, and that seemed to work at first but then went right back to 0.6 ft. I also tried lowering the surface clutter setting and that didn't work. Anyone else had problems like this?