There have been some recent posts about blockage in the cooling path from the factory. Take a good look at the cooling path especially if it has a roof vent. Some times they forget to remove insulation and stuff from under the vent. The installation manual that came with the RV should detail proper installation methods. Remember the unit must be fairly level to cool properly.
I just looked, we have a 2118 in our 17 Laredo, it has been on since May. it is set on 5 and will freeze stuff in the fridge if not careful. We use the RV every couple of weeks so we never unload it. It operates on electric most of the time as we have a hook-up at home. We let it do its propane thing going down the road. My wife purchased this unit because of the fridge.
Check the door seals, seams like we have to gently push on the right door after using the left door to get a complete seal.
BTW these are $3,500.00 refrigerators in the retail market, demand that it works correctly. We are very happy with ours.