If you enable this, then there will be a "Speed Icon" shown on the player.

Clicking on this icon will enable your visitor to increase speed* of audio playback.

(*Smart-Speed: Thanks to this feature of CoolCastPlayer, the sped-up audio doesn't just blindly speed up the audio, as that would make the speaker sound like a chipmunk. Instead, it only removes dead-air and silences to speed up the audio.)