Maybe the sight of the polis at their door will be enough to smarten up their act. You can also show the police you are a decent sort, don't want to waste there time but your at your wits end. I hate to add to your worries, but it's not going to get better itself. Im just saying what I would do. If you keep at the authorities, they will want it sorted, and if it's on record it is effecting your mental health, then they will have to do something.Even if they send police no doubt the noise would miraculously have stopped by time they arrive 2 hours later and I'm accused of stomping my feet on the floor to gain attention with recordings which are not trustworthy.