WE call this “brat dumping” and there is no reason you should have to put up with it as it is almost certainly breaching your by-laws, strata law and Environmental Protection laws.
Have a look at this factsheet, for starters. And have a look at this one (scroll down to the section on Noise Abatement).
According to this factsheet, noisy music has to be turned down by 10 pm. If they don’t, the miscreants could face noise abatement orders from the police and seizure of equipment.
I don’t know the details of WA strata law but I think you could go after both the residents of the unit for their behaviour and the owners of the unit for allowing it to happen.
Also, what do your by-laws say about nuisance?
Probably too late to speak to a strata lawyer but I would if I could.