Unprofessional landlord - how to BREAK LEASE?

The VAST majority of apartment walls are NOT soundproof!! Did YOU ask if they were sound proof? I have lived in some VERY nice apartments and NEVER lived in a place that was "sound proof". Sorry, but this is NOT a situation where you can break your lease. That would ONLY be possible if the lease SPECIFICALLY stated that the walls were soundproof, when in fact they are not. You cannot break a lease for not doing YOUR due diligence.