I have a huminbird 385ci combo on both of my ski's for the last few years and now both transducers seems to have failed. Mine actually failed last year and never got around to looking into why till now, now that the second has failed. I mounted them in the rear (in hull) beside the driveshaft. Do you think there is too much vibration or something back there? Strange how both quit so I'm thinking something isn't quite right. Would it work up front near the battery area or would it be in and out of the water when your bouncing around? Should I try a different transducer? Both ski's are 07 GTI 155's. Any info would be a great help.