I've tried just about all the remedies suggested in this thread, including replenishing washer fluid, "starting" without the clutch, changing key fobs to ensure a fresh battery, etc, etc. No luck so far.
I've noticed:
--I get the chimes at home invariably, upon opening the driver's door. The FiST is always parked in the garage next to my 2018 Shelby GT350.
--I only rarely get the chimes when I park at work in the garage beneath my office building.
--I invariably get the chimes when I park in the neighborhood shopping center.
--It doesn't seem to matter whether I've locked the car or not.
--I get the chimes when I open the driver's door, the passenger's door, the hood, or the hatch. I also get the chimes when I close the hatch or the hood.
--I get chimes often when I lock or unlock the Shelby, or close its hood. There is some electronic chatter between the two cars, obviously.
--From time to time, I get the chimes when I'm just walking through the garage.
I'l keep trying stuff.