It does look like that one, only one speaker failed. I tested wiring, Bad!Did you lose only one speaker or did you lose a pair? My last boat was a 2011 and the factory Sony stereo had an annoying default -- if the radio lost power, it would default to a 4 speaker set up. So both rear speakers would be silent. You had to drill down several levels in the settings to find the option to enable the rear speakers. So if your radio looks like this (sorry, I can't make out the model number in this crop), look in the manual for the setting to enable the rear speakers.
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