Personally, I would call Humminbird and send the unit to them. Their 1.83, 1.84, and now 1.91 software updates suck as lots of issues and you can read about them on bass boat central bbc.com, as they have a couple of postings and one is weeks old of issues, and now some of those members are being told, they can’t revert their depth finders back to older software versions once they install 1.91 software version. I just bought a new 7 mega DI for 2d and mapping and have it networked but haven’t been out in the boat yet to see if it works as they had 1.84 software installed on it from the factory new, and not sure if it will work even. If it is buggie, I will be raising he#* with Humminbird also. Humminbird definitely has some issues with upgrades in software and I am not upgrading my other 2 mega units as they work ok with older software versions on them. I know you have been having issues so I would call them. Good luck.