yes on the clucking. if it is allowable to have chickens you should be ok.I'm sorry to hear about your neighbor troubles. I've had plenty of my own. If you don't have any roosters you should be able to fight this thing and win it.
Go to Radio Shack and get yourself a measuring device for sound, I can't remember what its called. They'll know what it is. It measures sound in dB levels. In the package is a chart that gives normally acceptable noise levels all the way up to intolerable. Find out exactly how loud your clucking hens are. I'll bet its well within the acceptable range. Also, if you can prove how many birds you've sold since he first notified you of a problem, that will help. Take pictures of your clean pens/birds to show the judge. Isn't there an allowable number of hens you can have? If you're within your rights, and you can prove that they are not as noisy as he may claim, you should be good to go.
I've been to court over my birds, when I lived in California and I won my case with this information. I was within my allowed number of birds and I could prove they were not as noisy as the neighbor claimed. Right to Farm is on your side.
If he has to prove your birds are too noisy then you should still be ok, let him try, but in the meantime, arm yourself with what you can. Know the laws of your specific residential zone. "Chickens clucking at all times of the day" is not a noise violation. You have rights, you'll need to fight for them.
I wish you the best of luck.