I have worked as a repair tech for Xantrex inverter/chargers and though the unit is new, you could very well have a bad control board inside the unit. The new cards are being manufactured in China
and the quality control has not been so great. I have even seen new units come in with a strange sound occuring everytime the fan comes on. This is simply a lack of quality control and all it requires is a pair of scissors to trim the insulating paper away from the fan.
I would also advise placing the remote in ASAP because you have to program it for the type of batteries you are using. I am pretty sure Xantrex inv/chargers come factory set for wet-cell batteries. NOT GOOD IF YOU ARE CHARGING AGM
. Place the remote in, program it and see if the inv/charger still acts up. If so, I would bet you that the control board is bad.
Oh yeah, good luck with contacting Xantrex. You would have better luck contacting the international space station.