Sounds like you need to immediately stop using the inverter. Sounds like you have a loose wire, and that can cause heat, which can lead to a fire. Remove all power to the inverter, including battery power, shore power and generator power. Make sure the rig engine is off. Remove the access cover to the wiring input on the inverter and locate the loose wire. Using the proper tool, tighten all the connections, but don't overtighten them, as that can lead to connection failure. Once that is done, put the cover back on and reconnect power.
2006 Damon Daybreak 3276 35'. 3 200 Amp Lithium batteries and 2000 watt Pure wave inverter/charger.
2013 Elantra on a Master Tow dolly.