I just moved into a new apartment complex about two weeks ago. Pretty much the first day we got there we were playing music and the person above us started banging on the ceiling. Mind you, it was in the middle of the day and the music wasn't very loud. For the next few days the same thing happened and then we got a written noise complaint from the landlord. I've invited my neighbor and landlord to come to the apartment to listen to the stereo at the level we have it set, yet they refuse. Now what?
Quiet as a Mouse
It sounds like your neighbor is an old biddy with too much time on her hands and your landlord is lazy. I suggest you ask your surrounding neighbors to come and listen to your stereo and then sign a letter stating that they have no issues with the volume you have it set on. Once you have that, write a letter to your landlord and neighbor making it clear that you've tried to invite them over for a discussion in order to find a compromise for the situation- yet have been refused. Include the signed statement from the other neighbors and then add that you feel, from this point on, any banging and disturbance from your upstairs neighbor will be deemed harassment. That should cause your landlord to stop by.