Issues with new installation

[Air-Sea]

Issue 1:

The depth finder worked perfectly for the first month, then I noticed a periodic blank (--) in the depth data box. Selecting the fish finder mode I noticed multiple slices of the graphic display sometimes five to ten. It always worked at the slip in approximately 12 feet of water with the engine either ON or OFF. It seems to have progressed to where it will only work when I select the ‘down vision’ channel, but quickly goes away on the chart plotter screen.

Attached is a drawing of the Raymarine electronics installation.