I am running a 125 watt solar panel on our '09 3670 Big Horn. I installed a Prosine 2000 watt pure sine wave inverter/charger and a Blue Skies controller. I use 4 - 6Volt Golf Cart Batteries and have never had a problem. I installed a 30 amp sub panel which has breakers for the bedroom, kitchen and entertainment center. The Prosine senses shore power from a 30 amp breaker on the main panel. I have a signal booster for my air card which is on all the time. Both of our TVs are on standby power. the fridge uses battery power and so do our clocks so we have a fair bit of parasitic draw but it has never been a problem for my panel. We have watched TV for several hour using our satellite dish and TV on inverter and used our coffee maker in the morning as well as used the microwave. If the batteries are not holding up, assuming that the terminals and connections are corrosion free and tight, I would load test the batteries to see what shape they are in. I would check my controller input voltage and as has been mentioned checked for loose or corroded connections. High resistance form these can cause lots of problems. If the panel is producing to its nominal capacity and the controller is regulating properly, the batteries may be on their last legs.