 While the band worked on The Notorious Byrd Brothers album throughout late 1967 , there was increasing tension and acrimony between the members of the group , which eventually resulted in the departures of both Crosby and Clarke . McGuinn and Hillman became increasingly irritated by what they saw as Crosby 's overbearing egotism and his attempts to dictate the band 's musical direction . In addition , during the Byrds ' performance at the Monterey Pop Festival on June 17 , 1967 , Crosby gave lengthy in @-@ between @-@ song speeches on controversial subjects , including the JFK assassination and the benefits of giving LSD to " all the statesmen and politicians in the world " , to the intense annoyance of the other band members . He further irritated his bandmates by performing with rival group Buffalo Springfield at Monterey , filling in for ex @-@ member Neil Young . His reputation within the band deteriorated even more following the commercial failure of " Lady Friend " , the first Byrds ' single to feature a song penned solely by Crosby on its A @-@ side . 
