I have a multiplus 2 with 4 lion UT1300 bateries (420ah) a lynx distributor and a victron bmv 712 monitor. Everything has operated flawlessly until I added the ve bus smart dongle. After adding the dongle I get voltage fluctuation from around 13.5 - 15.1 volts. When I unplug the dongle the voltage stabilizes to match my charger configuration. Does anyone have a suggestion.