Le_37, when people make so much noise, it's clear that they just don't care so talking to them won't help. Come down hard on them and call southwark's noise team. They'll get a warning and if they continue making noise, their stereo will be seized. Also worth finding out who their landlord is and making him aware that their tenants are causing huge disturbance. A landlord has a duty to ensure his tenants behave. Good luck.