We had similar depthsounder problems last summer cruising to the Broughtons in our 2016 R29. The depth reading would become intermittent or just go flashing and required a system reset. As we were getting ready to run the first of the 3 rapids, it went out entirely and wouldn't come back. My wife ran the boat through the rapids with no depth reading while I stood on my head in the rear cock pit fixing the transducer, awkwardly located in the bottom of the rear compartment right under the stern thruster motor. I found the cap was loose, the cup was full of dirty water, and the O-ring was in the bottom of the cup. I cleaned it up, filled it with water, and got the O-ring back in place; but the lid would not stay on, it kept popping loose on one side. I finally determined that the tabs and/or grooves that lock the lid on were worn. I took a piece of plastic grocery bag, folded it a few times, and placed it between the lid lock tabs and the cup. The lid stayed on and we had sonar readings for the rest of the trip. I found some pink RV antifreeze for it up in Sullivan Bay, but haven't yet found a more permanent solution for the lid. Hoping not to have to peel the cup off and replace the whole thing.