Increasing drug use also affected Bruce's health. By 1966, he had been blacklisted by nearly every nightclub in the U.S., as owners feared prosecution for obscenity. He gave a famous performance at the Berkeley Community Theatre in December 1965, which was recorded and became his last live album, titled "The Berkeley Concert"; his performance here has been described as lucid, clear and calm, and one of his best. His last performance took place on June 25, 1966, at The Fillmore Auditorium in San Francisco, on a bill with Frank Zappa and The Mothers of Invention. The performance was not remembered fondly by Bill Graham, whose memoir describes Bruce as "whacked out on amphetamine;" Graham thought that Bruce finished his set emotionally disturbed. Zappa asked Bruce to sign his draft card, but the suspicious Bruce refused.