One day after Jay Z’s streaming service Tidal celebrated its one-year anniversary, the rapper-turned-businessman is taking legal action against the company that sold it to him.

Jay Z paid $56 million last March to acquire Tidal from Swedish-based technology company Aspiro. Tidal said Thursday it has served legal notice to the parties involved in the sale after an internal audit found that the streaming service was not as popular as it had been led to believe at the time.

“It became clear after taking control of Tidal and conducting our own audit that the number of subscribers was actually well below the 540,000 reported to us by the prior owners,” the company said in an emailed statement.

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Since its launch last year in New York City, Tidal has been rather tight-lipped about its progress, subscriber numbers and acquisition rumors. But the service said this week it now has more than 3 million subscribers globally. By comparison, Swedish music-streaming platform Spotify AB, which was launched in 2008, said it took 5½ years to reach 10 million subscribers. Spotify said last June it had hit 20 million subscribers.

For Tidal, its first year under new ownership has been marked by criticism and the departure of five executives. Chief Investment Officer Vania Schlogel confirmed her resignation in November. In December, Tidal hired Jeff Toig to become its third chief executive after eight months under Jay Z’s leadership. Most recently the company parted ways with its chief financial officer, Chris Hart, and chief operating officer, Nils Juell.

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Tidal, which provides high-fidelity, or lossless quality audio, touts itself as a champion of artists. The service launched with 16 artists as equity owners. It offers subscribers exclusive behind-the-scenes and video content, as well as exclusive album releases, such as Rihanna’s “Anti” and Kanye West’s “The Life of Pablo,” all for a price of $20-a-month for a high-quality subscription, or $10 for a standard subscription.

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