Jazz musician Al Jarreau, best known to TV lovers as the smooth voice behind the theme song to the mystery drama series Moonlighting, died Sunday. He was 76.

Jarreau's team had announced his retirement from touring on Wednesday through his official social media channels, revealing that he was in hospital treatment for exhaustion and was, at the time, "improving slowly."

The singer was reportedly showing signs of improvement and even treated the nursing staff to a rendition of his famed number for Moonlighting, which ran for five seasons in the late '80s with Bruce Willis and Cybill Shepherd in the lead roles.

However on Sunday, his reps confirmed on social media that Jarreau passed away at the hospital of unspecified causes while surrounded by his loved ones.

In addition to his film and television soundtrack credits, Jarreau, known to many as "The Acrobat of Scat," was also occasionally seen in cameo acting roles, including a 2014 episode of The Soul Man, in which he played himself accepting one of his seven Grammy Award wins in place of Cedric the Entertainer's Boyce "The Voice" Ballentine.

Jarreau was a prolific and celebrated jazz musician, who released 16 albums between 1975 and 2014. Two of his nearly two dozen Grammy nominations were for his work on the Moonlighting theme, as he was nominated for Best Pop Vocal Performance by a Male and Best Song Written Specifically for a Motion Picture or Television in 1988.

Jarreau's death has prompted an outpouring of social media remembrance from fans and celebrities were inspired by his prolific and celebrated career.