798ci hd fishfinder combo
The 798ci 2d sonar doesn't seem to read depth or show the correct depth in the display no matter if I'm at high speed or drifting. It fluctuates around 5.6 feet. If I'm looking at the down imaging I can see the depth change but still reads in the 5.6 foot range. I do have the shoot through transducer installed, not sure of the model number. However it was installed together at Master Boat Repair so I'm confident the right one was installed. I've ignored it for a long time now and want to get it fixed. Could it be something in the menu, the unit itself, or the transducer?