Liberty Media is the majority owner of SiriusXM, and CEO Greg Maffei has been open about his interest in Pandora.
"Pandora actually under-monetizes on its listening hours ... it has a superior product to many of the other free services," Maffei said in a Liberty Media earnings conference call on May 9.
Pandora posted mixed quarterly earnings on May 8: The streaming company posted an adjusted loss of 24 cents per share, excluding items, on revenue of $316 million. That's compared with 34 cents per share on revenue of $318 million expected by a Thomson Reuters consensus estimate.
But while Pandora Premium's March launch is already yielding results, according to founder and CEO Tim Westergren, Pandora's active listeners were 76.7 million at the end of the first quarter of 2017, down from 79.4 million a year ago.
KKR — an investment firm known for its private equity and hedge funds — plans to invest $150 million in Pandora in exchange for new shares of preferred stock. But sources familiar with the company's thinking have previously told CNBC that Pandora is confident it can come to an agreement to sell itself before the KKR investment closes.
Despite increasingly fierce competition from Amazon, Apple, Spotify and Google, Pandora remains a popular business. It's been the No. 1 grossing music app every day in Apple's App Store for the past six months with the exception of five straight days in November when Spotify took over, according to research from Apptopia.
— Reporting by CNBC's David Faber on "Squawk on the Street." Written by Anita Balakrishnan.