I'm actually not sure. If the source of the noise is coming from a house, you can get warnings from the police and end up being evicted.
The only laws I can think of that may apply are disturbance of the peace stuff, but that's intended for more malicious acts. I actually would not call any kind of law enforcement for this though, because there have been severe police cuts across the country and my area specifically has been badly affected. Even community support officers are few and far between here.
That might be another difference. By-law is not usually handled by police here. There are by-law enforcement people, similar to meter-maids, that deal with it.
They are particularity effective against businesses, as fines scale up exponentially, and failure to pay results in the loss of a business license.
Considering it is very effective, with a net cost of little to nothing (fines in largely cover operational costs), I'm very surprised you don't have the same.
Unless that's what you mean by 'community support officer'. We have a similar named position, but I don't think it's the same thing.
PCSOs are nicknamed "plastic police" here. They are part of the police force but are not "real" police officers. Their powers are limited, they can't arrest people for example, but they can detain you for half an hour while an actual police officer arrives. They are not actually allowed to physically restrain you though, so you can run away. I imagine there are certain cases where they would be authorised to use physical force for detainment though.
They deal with small disturbances and are kind of like scouts, patrolling around areas for no reason in particular. So I think they are similar to what you're describing.
Is that legal?
We have noise limits depending on zone and time. You can't rock a party bus in a residential neighbourhood.
If it was here I would suggest recording the van, with the logo and noise, and send it to by-law enforcement.
Not sure how that would/wouldn't work in your area.