With all that is going on there nightly, the police is not doing it's job. They should send some under-cover agents there one night to spend a couple of hours observing the goings-on. By your description, they will be able to make some busts.
More generally:
Can we perhaps get the City Council to enact a more effective noise ordinance, on behalf of residents? Isn't that what they are there for, if enough people need resolution to this type of problem?
Personally, though this pales in comparison to the other problem, I do not appreciate the regular Friday morning 6:20 AM leaf blowing in the back yard of my neighbor, as the hired landscapers get an early start to their work day. I have often wondered if it's legal to make that much noise that early in the morning. I'm sure other people have other examples of too much noise late at night or early in the morning.