I agree that the idle popping is usually not a big deal as long as it is minor popping. To cure it, you need to take apart the turbine and re-point the fuel needles (the ones on the vaporization tubes that are dripping) so that they are squirting fuel properly into the vaporization tubes in such a way that you get full vaporization before the fuel/air enters the primary combustion zone. Best left to an expert on that engine.