City chairman Nguyen Thanh Phong said at a meeting on Friday that he has received numerous complaints about the din caused by the portable loudspeaker and wireless microphone, especially after 10 p.m.

"People work hard all day and it is unacceptable that they come home only to be tormented by such noise. Local authorities and related agencies should take responsibility for this situation, which should not be considered a normal occurrence."

Mobile karaoke is often seen at street restaurants or cafes, operated by a pair, of whom one member would be singing songs and the other trying to sell snacks among the diners or drinkers. They can also rent out the tools to some patrols to sing on the spot.

Phan Dinh An, chairman of Ward 6, Go Vap District, said local authorities could not deal with the problem because they have no means to measure the volume of the noise.

He wanted the city to mandate the use of specific software or apps by local authorities to measure the noise.

Vo Trung Truc, deputy director of the Department of Natural Resources and Environment, said it should be noted that karaoke noise does not just come from the street karaoke service, but also many households.

His department would set up a team with police officers to fine people causing too much karaoke noise.

City deputy chairman Vo Van Hoan said the laws related to noise violations are specific but their application and the accountability of agencies are confusing, he pointed out.

He said the environment department should be the main agency handling the problem and it has to take into account all existing regulations and draw up specific guidelines for various agencies and local authorities.

The mobile karaokes have sparked a lot of fights over the noise, even resulting in deaths.

Last October, a man in the southern Dong Nai Province was stabbed to death by his neighbor for singing karaoke loudly until near midnight, and reactly aggressively when asked to stop. Similar incidents have been reported often.

To Thi Bich Chau, president of the city Fatherland Front Committee unit, which monitors the city government's activities and policies on behalf of the public, said at a meeting last year that one of the reasons why the problem persisted was the lack of strict and resolute action by local authorities.

Huynh Thanh Nhan, director of the Department of Culture and Sports, had said then two inspection teams had been formed to tackle the problem, but dealing with noise pollution was the police’s responsibility.

And the police had failed to take stringent action against offenders, he said.

The problem has to be tackled forcefully at the district level, he said.

The government issued a decree in 2013 that imposes a fine for causing "loud noises, making noises, or commotions in residential areas or public places between 10 p.m. and 6 a.m." but the fine of VND100,000-300,000 ($4.33-13) has been criticized as being too paltry.