Is your converter fan cycling?
On my Thor, Four Winds, 06 Hurricane, the interior lights would dim and bright about every 10 seconds. When they brightened, I could here the fan on the converter come on. Then when the lights dimmed, the fan would go off. Changed my converter. Fixed the problem.
06 Hurricane 34FT WH W20 Chassis 8.1L 132K, Steersafe, Koni Shocks, DIY Trac Bar, Tri-Metric 2025RV Battery Monitor, 4-6V Batteries, Scan Gauge 2, Crossfires, 735W Solar Morningstar MPPT-60, WG T4 In-Motion Sat, XM Radio, 07 Chevy Malibu Maxx Toad, Falcon 2, Brake Buddy, Escapee