Grammy-winning singer, songwriter, and composer Isaac Hayes died in Memphis on Sunday. He was 65.

The music legend was found unresponsive near a treadmill at his home, investigators say. He was pronounced dead an hour later at Memphis’ Baptist East Hospital.

Hayes won a Grammy for the “Theme From Shaft,” but was well-known to younger fans as “Chef” on the popular Comedy Central series, South Park.

He had also filmed a cameo role in “Soul Men,” a film due out later this year alongside Bernie Mac, who also passed away over the weekend.

Isaac Hayes would have turned 66 on August 20, He is survived by his fourth wife, 12 children, and 14 grandchildren.