In 'Thank You, Jeeves', Jeeves temporarily leaves Bertie's service because he cannot tolerate Bertie's constant playing of the banjolele (a banjo-ukulele hybrid). This drives Jeeves to give notice, leading to one of the few times they separate. The purple socks and cruise references are from different stories, and while Jeeves does consider Bertie 'mentally negligible', he's too professional to leave over that.