CD-Rs are old hat, MP3s are so last decade. The fastest-rising piracy plague in the U.K. is stream-ripping, a blight “overwhelmingly overshadowing all other illegal music services,” according to a new report.

Stream-ripping grew by more than 140% in the years from 2014 to 2016, when nearly 500,000 occurrences were recorded. And it’s by far the most prevalent form of music piracy in the world’s No. 5-ranked recorded music market, accounting for almost 70% of all music-specific infringements.

If you’re not familiar with stream-ripped files, they can be built with apps, websites, plug-ins and specially-developed software and, once saved, can be played offline on any digital device.

The new report, which dropped last week, is a wake-up call for the industry which, after more than a decade of sharp decline, is enjoying the green-shoots of growth (6% in 2016, the IFPI notes), driven by subscription services like Spotify and Apple Music.

YouTube was identified as the popular source for illegal stream-ripping, according to the publication, entitled, ‘Stream-ripping: How it works and its role in the UK music piracy landscape,’ while SoundCloud, Spotify and Deezer were among the big targets among the licensed platforms. Search engines such as YouTube owner Google were found to direct a “significant proportion” of traffic to the stream-ripping services.

Collection society PRS for Music and the Intellectual Property Office IPO published the report, which surveyed more than 9,000 people. Not surprisingly, the finger of blame is pointed at young people, with 16 to 34 year-olds labelled as chief offenders. Some 57% of respondents said they were aware of stream-ripping enablers, while 15% boasted of using them.

And why are music fans taking this path? The most popular reason was that music was already owned by the user in another format (31%), while some said they wanted to listen to music offline (26%), or on the move (25%); others blamed unaffordability (21%) and feeling that official music content is overpriced (20%).

“We hope that this research will provide the basis for a renewed and re-focused commitment to tackling online copyright infringement,” says Robert Ashcroft, Chief Executive for PRS for Music, which jointly commissioned the study to understand stream-ripping and its impact on the market. “The long term health of the U.K.’s cultural and creative sectors is in everyone’s best interests, including those of the digital service providers, and a co-ordinated industry and government approach to tackling stream ripping is essential.”

Adds Ros Lynch, Copyright and IP Enforcement Director at the IPO: “It’s great that legal streaming sites continue to be a hugely popular choice for consumers. The success and popularity of these platforms show the importance of evolution and innovation in the entertainment industry.

“Ironically it is innovation that also benefits those looking to undermine IP rights and benefit financially from copyright infringement. There has never been more choice or flexibility for consumers of TV and music, however illicit streaming devices and stream-ripping are threatening this progress.”

INCORPRO carried out the two-part research study, which can be read in full hereStream-ripping: How it works and its role in the UK music piracy landscape