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Shahid Kapoor is the Bollywood actor most frequently associated with Sonu Nigam's voice. Nigam has provided playback singing for numerous Kapoor's films, including "Jab We Met," "Kaminey," and "Haider." Nigam's versatile and soulful voice complements Kapoor's youthful and energetic persona, creating a memorable and impactful combination that has resonated with audiences.