I tried to upgrade from 5.3.1 to 5.6.0. After the original load, I ran into the "NO GPS INPUT DETECTED" error. I erased the EEPROM and rebooted the box, and then all of the sudden it received the GPS input, however, the UAT wasn't fully configured due to the EEPROM being erased. I was able to put in my N-Number into the first configuration tab, and after a power cycle I could get a GPS signal. However, as soon as I changed any setting on the INPUT tab (Altitude Encoder or Transmitter Control Panel), the GPS would report back all 0's for LAT and LONG. The only time I can get the unit to fully work is after a EEPROM erase, I can enter in all of my pertinent information and it works...until I have to reboot the device and then it never gets GPS signal. I have loaded the new firmware at least 10 times from multiple different computers (Microsoft Surface and a Dell Laptop) to no effect.
I would warn people from upgrading to 5.6.0 until this bug has been worked out of the firmware. I will call Bill up Monday to get some support.
For the record, I am using a Garmin GTX327 as my Transmitter Control Panel type, and using the Shadin-Z Altitude encoding protocol at 9,600 bps.