Shares of the New York-based company rose 4% to $6.64 on Tuesday.
Sirius reported net income of $433 million, or 10 cents a share, compared with $243 million, or 5 cents a share, a year ago. Revenue totaled $2.16 billion, up 15% from a year ago.
Revenue growth was driven by a 4% increase in SiriusXM's average revenue per user to $14.57 and a 3% increase in SiriusXM self-pay subscribers, the company said.
SiriusXM added 355,000 net new self-pay subscribers in the second quarter, up 34% from a year ago. Paid promotional subscribers decreased by 378,000.
Total subscribers at the end of the second quarter were 34.5 million, up 1% from a year ago.
Second-quarter ad revenue at Pandora, which includes off-platform results such as the company's AdsWizz business, increased by 82% year over year to $383 million.
"The quarter was bolstered by record self-pay churn of just 1.5%, and we achieved strong monetization in our advertising business, with an increase in ad revenue of 82% from the prior year period and 20% from the second quarter of 2019," said CEO Jennifer Witz, who was named to the top spot in September, replacing Jim Meyer.
Looking ahead, Sirius said it expects net subscriber additions of about 1.1 million and total revenue of about $8.55 billion. Analysts surveyed by FactSet are calling for full-year revenue of $8.42 billion.
The company expects adjusted EBITDA of about $2.675 billion and free cash flow of about $1.7 billion.
In December, SiriusXM signed prominent talk-radio personality Howard Stern as producer and host for another five years.
Sirius XM's exclusive rights to Stern's audio and video archives will continue for an additional seven years, the company said.