T@b400 Inverter

While vacuuming our 400 using the inverter plug, after returning home from a wonderful week at üCamp18, the inverter went into "AC" mode and is not seeing DC input.  The vacuum we were using is well within the 1400 +-200 watt inverter capability as indicated in the manual.  The vacuum ran fine for most of the cleanup and was really never run for more than a few minutes at a time.  The vacuum was kept plugged in, and when turning it on for the 3rd or 4th time, the inverter switch showed AC vs DC mode. Battery voltage never dropped below 13 volts at the inverter.  The blade fuse on the positive battery cable, coming into the inverter, is good as well.
We contacted our dealer to report the problem and also contacted Tech at nüCamp, who gave us the number for Aimes Power, the manufacturer of the inverter.  Aimes suggested doing a factory reset which entails disconnecting the inverter from the switch and all power input, leaving the inverter sit for an hour and reconnecting the power and switch. 
Sadly, that didn't work, so we will be calling Aimes Power on Monday.  In the mean time, has anyone had a similar issue with their 400 inverter?