Hi, ive actually been through this with a noisy/anti-social neighbour. As others have stated, start to keep a diary of all incidents that happen, contact your local environmental health team and they will send you out some diary sheets to complete. Once they have reviewed your diary entries they will send out someone who will then talk you through the whole process and in my case installed a sound recorder device, this was in my flat for a week on two occasions. This will pick up not only levels of music but also shouting/banging etc, it had two microphones fitted. Once the data recorded is collected and anaylsed the EH will decide what steps to take, in my case they liased with my housing association and issued a noise abatement notice.They also gave me a special number that i could call 24hours a day for someone to come out to witness the noise etc. The notice issued didnt stop anything in my case but it allowed the housing association to start the eviction process, my neighbour was evicted and now resides at Her majesty's pleasure due to other activities! This is a slow process but local councils take anti-social behaviour very seriously now, its high on their list of issues to tackle and it is well worth doing. I cannot say how much of a difference it has made to me now and it feels like a huge weight has been lifted. Good luck and i hope you manage to get this resolved!