Dometic 3-Way Refrigerator in a 22 Sport

[JeffofCT]

My 3 way fridge is underperforming while on propane. It appears to keep trying to light every 10 seconds or so--even though the burner IS lit. Eventually, I get an fault error and the fridge performs at about 53 degrees F.

I have cleaned the burner, including the flute just as I've done in the past. Fridge works fine on 12v and 110v.