RV Oven Flashback

My propane RV oven experiences regular flashbacks to the air shutter at the back of the oven. I have tried adjusting the shutters to no avail. Any suggestions on how to fix this?
Waldo, (Palm Springs, CA) 

Waldo, the first thing to check (or have verified) with any propane appliance issue is the delivery line pressure. Too low or too high LP pressure can cause a plethora of operational issues with any and all of the four propane-burning appliances. It’s quite possible the delivery pressure is set too high. Setting the pressure to the correct level necessitates the use of a manometer which any certified RV service tech will have. 

Once the LP pressure has been set to 11.0 inches of water column, the next item to check would be the cleanliness of the main oven burner. Most can be removed with relative ease. Inspect each of the holes in the burner. Look for plugged ports, soiling by cooking greases or possibly an accumulation of oven cleaner or other debris blocking some of the ports.

Next, though in the oven it’s rarely adjustable, check that the oven burner assembly is in alignment with the orifice fitting at the safety valve near the back of the oven. Any misalignment may cause turbulence inside the mixing tube, much akin to a related problem associated with the water heater. The incoming propane draws in air from inside the oven to be mixed prior to it being consumed by the burner. 

Another item to check is the orifice fitting itself. It can be removed, soaked in acetone or a like liquid and then allowed to air dry. Much like the ports in the burner, it is possible cooking oils may have partially blocked the oven orifice. 

Finally, the air shutter should be adjusted so that the main burner flame is steady, with sharp blue points and not lazy or “floating” above the ports. One other cause of your symptom may be a damaged or bent burner assembly. But a close inspection will reveal if that’s the case.