I wonder if anyone can help on this issue which seems to have defeated Furuno who say they haven't come across it anywhere else.
I have dual MFD12's with Furuno GPS, AIS and Hub. Speed, Depth, Wind and Autopilot sit on a B&G Hydra network with a NMEA 183 Mux and Splitter handling the interconnection of the two networks. Routes are developed on a pc running MaxSea TZ and uploaded to the MFD. The pc is then closed down on passage to save power.
When following a route the MFD alarm sounds four times on mark/waypoint arrival, the banner at the top of the screen goes from yellow to red while the alarm is sounding and the MFD then shows the next leg as 'active'. The next leg needs to be set on the autopilot via the B&G GPD. So far so good.
Occasionally and here is the problem the alarm simply doesn't switch off, the banner at the top of the MFD stays red (and blinks slightly) and the alarm goes on and on and on. Pressing the cancel button has no effect and we normally have to turn the alarm to silent to kill the noise. At some point on the next leg the system sometimes re-sets itself to normal but this is not always the case and we normally find we have to turn the sound off for our own peace of mind.
The problem is intermittent. Some days it doesn't happen but on other days it's quite persistent. The only slight suspicion is that it happens more often when waypoints are closer together than not but I'm not 100% sure of this.
Furuno suggest upgrading to v2.07 software and wonder if the MFD's might be faulty. Both long shots I think as the fault can happen on one or other MFD so unlikely that both are faulty and exhibiting a fault not seen by them anywhere else. Ditto I wonder if the software update will fix a hitherto unreported problem.
Any ideas/possible lines of enquiry gratefully received.