Neighbor is harassing is, dont know what to do anymore?

OK so ever since we moved into our new house, we have been getting complaint after complaint, it started when we moved in and had a few bags of cloths and boxes of unpacked things because well we had just moved in, he called our HOA about it and even went over our wall to take pictures trying to say they were bags of dog crap, he started placing a speaker in his window, doing a loud chirping sound, we have called the police 3 times on him and had 2 reports on him, the last time we called the police they went and had a talk with him and now he no longer dose the speaker but now he is calling the police and animal control for noise complaints, he called animal control on us on my sisters graduation and then called the police on us the last 2 days in a row, he is doing nothing but harassing us, none of our other neighbors have a problem with us, even the one next door to us with children said she never even hears us, the guy thinks we are renters and has sent 3 harassment letters to both this house and to our old house, we are at a loss, i mean i don't know what else we can do here, someone please help