“Recife’s Mayor’s Office, via the Secretary of Mobility and Urban Control, started this Tuesday (2nd) removal and confiscation of speakers installed on light posts in Recife. São José and Santo Antônio will be the first neighborhoods to benefit from the intervention, locations that account for 30 such speakers installed without the city’s authorization.
The act will have the support of Pernambuco’s Military Police (PMPE), the Company of Urban Servies of Recife (CSURB) and the Company of Urban Cleaning of Recife (EMLURB). After the removal, the speakers will be taken to the CSURB deposit, in Santo Antônio.” 
In previous years, the Recife government started a campaign called “Som Sim, Barulho Não” (Sound yes, Noise no) which you can learn more about here (PT). Below, you can see an educative video talking about noise pollution in the city.
If you’ve lived in Brazil, you know that public speaker systems (mobile or stationary) are really annoying. If you’re interested in knowing what the population of Recife thinks about noise pollution, you can read about it here or here (both in PT).