In the age of podcasts and streaming services, you might think pirate radio is low on the list of concerns of US federal lawmakers and broadcasters. You'd be wrong.

They are increasingly worried about its presence in some cities, as unlicensed broadcasters commandeer frequencies to play anything from Trinidadian dance music to Haitian call-in shows.

They also complain that the Federal Communications Commission can't keep up with the pirates, who can block listeners from favorite programs or emergency alerts for missing children and severe weather.

Helped by cheaper technology, the rogue stations can cover several blocks or larger areas. Most broadcast to immigrant communities that pirate radio defenders say are underserved by licensed stations.

"The DJs sound like you and they talk about things that you're interested in," said Jay Blessed, an online DJ who has listened to various unlicensed stations since she moved from Trinidad to Brooklyn more than a decade ago.

"You call them up and say, 'I want to hear this song,' and they play it for you," Blessed said. "It's interactive. It's engaging. It's communal."

Last year, nearly three dozen congressional members from the New York City area urged the commission to do more about what they called the "unprecedented growth of pirate radio operations".

The National Association of Black Owned Broadcasters made a similar appeal, saying that pirates undermine licensed minority stations while ignoring consumer protection laws that guard against indecency and false advertising.

The New York State Broadcasters Association estimates that 100 pirates operate in the New York City area alone, carrying programs in languages from Hebrew to Gaelic to Spanish.

Commission chairman Tom Wheeler cited a stagnant budget and the smallest staff in 30 years. He said fines and seizures are not enough, because pirates often refuse to pay and quickly replace transmitters and inexpensive antennas.