2013 8.2L mercruiser alarm diagnosis

I have a 2013 8.2 L mercruiser that is sounding 6 beeps every 5 to 10 minutes when at cruising speed. I took the boat to multiple dealers and all indicate there are no active faults. I called mercury and they are investigating from the last data pull from a dealer with the laptop. The boat has medallion gauges and the only visual indication is the tilt indicators goes to zero coincident with the 6 beeps. It returns to the proper trim indication about 1 minute later. The out drive moves up and down even though the tilt indicator does not move. People are guessing it is a can bus communication error. Anyone with this type of problem or that can point me in a direction on how to diagnose this would be greatly appreciated. The timely nature of the alarm points me in another direction from a wire issue.