Possible Clues:

• Double act
• The Swell Season, e.g
• Husband-and-wife team, e.g.
• Daft Punk, for one
• Singing couple
• The White Stripes, e.g.
• Pet Shop Boys, e.g
• Sonny and Cher, once
• You, me and a mike
• Key and Peele, e.g