P!nk spends a second week at No. 1 on the Billboard Hot 100 with “Just Give Me a Reason,” featuring fun.’s Nate Ruess. PSY, meanwhile, soars 12-5 with “Gentleman,” which adds increased streaming and sales to its already record-setting YouTube views totals. “Reason” reigns on Hot Digital Songs for a fourth week with 262,000 downloads…

One rock band replaces another atop the Billboard 200 as Fall Out Boy’s Save Rock and Roll debuts at No. 1, bumping last week’s champ, Paramore’s Paramore, down to No. 12. Fall Out Boy bows with 154,000 sold, according to Nielsen SoundScan, the quartet’s third-biggest sales week ever. Only the No. 1 arrival of Infinity…

Pop star Katy Perry has struck back at the hair-styling company that rushed into court April 11 in anticipation of being sued over an endorsement contract. Two weeks ago, Jemella Group Limited sued Perry’s loan-out company, Killer Queen LLC, contending that it had paid the singer $4.5 million under a two-year deal to endorse GHD…