I live in a rural area in a mobile home in a very nice mobile home park. We each have a decent sized yard and a decent amount of space between each home, so you don't feel like you open your door to go out and are right in your neighbor's door to go right in. lol
So, Molly doesn't hear much other noise most of the time. It is quiet here. Even pretty much so in the summer time when the kids are out.
When Molly does bark (almost 100% of the time), it's usually at one of my cats as she wants to play with them. The cats themselves are young too at 1 years of age. But they are persians, and their job in life is to look beautiful at all times as they lay about luxuriously decorating the furniture and room.
So, if the cats don't instantly get up to play (afterall they have to look dignified at all times and "playing" is beneath them.) , Molly barks. I do tell her "no" firmly and "stop that". I then ignore her and refuse to acknowledge her until she stops. She is slowly getting better at the barking. She's not doing it quite as bad now.
However, I don't have any other suggestions except what others have already said. Good luck as I know it can be annoying at times.