Call the city code enforcement office and report the number of people living there, see if they want to do anything (you can not force them). You can have a lawyer send a cease and desist to the neighbors regarding their noise and see if that gets their attention. The lawyer can also send a legal letter to the landlord/management if he/she feels it is warranted. You do not say enough about what kind of noise this is (kid noise for example, usually is not actionable, while animals and music is). You could sue them for Nuisance and Interference with the Right to Quiet Enjoyment in small claims court. A reasonable person standard is used--the Judge would have to believe a reasonable person would find the noise so unbearable it would deprive them of the joy of their living space. People's sensitivities are not taken into account. You can also request the management move you. You could also take your lease to a landlord/tenant attorney for advice on breaking it--never do this on your own.
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