Quacks and short 3-4 note greeting/pleading calls will kill ducks. You don’t have to be able to feed chuckle and blow a 20 note high ball. I see Athens in your location, go to the wheeler refuge visitor center and watch/listen to ducks this winter at the observation tower. Watch real ducks on youtube, not just people calling. If you want to know what not to do, then go to Swan Creek opening morning.