Satellite and Internet radio services would be required to restrict listeners’ ability to record and play back individual songs, under new legislation introduced this week in the U.S. Senate. The rules are embedded in a copyright bill called the Platform Equality and Remedies for Rights Holders in Music Act, or Perform Act, which was reintroduced Thursday by Sens. Dianne Feinstein, Lindsey Graham, Joseph Biden, and Lamar Alexander. They have pitched the proposal, which first emerged in an earlier version last spring, as a means to level the playing field among “radio-like services” available via cable, satellite and the Internet.