I found out the hard way what this message means and how to fix it and prevent it from happening again. After upgrading to the latest firmware (18.104.22.168 as of this writing), I flew the full duration of one TB48 battery with absolutely no problems at all. I've developed the habit of changing out each memory card with each battery change. When I put in a different card and battery, I got the loud single beeping, and the cryptic message "MC Connection to Center Board Failed". After going home to troubleshoot, also got the messages, "Gimbal Cannot Receive MC Data" and " Unplug 8 pin line between Damping Plate & Aircraft. 8 Pin Connection Loose". It goes on to tell you to restart the aircraft and if that doesn't help, call Customer Service. It turns out that the card I put in for the second flight still contained the .bin file for a previous firmware version. Plus the combination of already having the controller powered on, really confused the Inspire while it tried to read the firmware file. It locked up completely and would only emit the loud single beep. Couldn't even get it into travel mode to put it away. The way to fix this is to start with a memory card that has the current firmware on it and do a firmware "upgrade" like you are supposed to, meaning with the controller off. It is very hard to hear, but the Inspire will be doing the "dit dit dit dit" beeping from the gimbal even while the aircraft is doing the much louder single beep the whole time. After the update is complete, the single beep will go away and you'll be able to hear the " dit - dit dit" that lets you know it's finished. After that, you are back ready to fly!! To prevent this from happening again, be sure to remove the .bin file from all your memory cards after finishing any future upgrades.