[CA] depth keeps dropping out

[oldersalt]

I have a new Axiom 12. To save a bit of money, I had the local dealer install an in-hull transducer (i.e. mounted inside the engine room, shooting through the fiberglass hull (not sure if the hull is solid fiberglass or cored with something). As a non-fisherman, I am really only interested in getting a numerical depth reading (though the depth displays are fun to look at sometimes!).

The depth always comes on when the system is energized, but always drops out after I am underway for awhile. Restarting the Axiom brings the depth back, but then it disappears again after several minutes. MFD will say, when asked, "Transducer not found" or maybe "not connected."

Thoughts about possible causes and cures? I'm assuming the installer glued it down properly, and with my slow-moving trawler with the transducer located 1/3 back from the bow, I can't imagine it is losing the signal because of non-laminar water flow.

Thanks in advance for your suggestions.
Oldersalt