Season 4, Episode 5: "Local Ad" (13:43)
Michael often lets his racism and sexism slip out through insipid dog-whistle comments like "this is not my music." This is Michael at his most Karen...not, like, Rashida Jones's Karen, but the "I want to speak to the manager" / "Help, bird-watcher!" kind. He can't stand the idea of the branch being represented in any voice aside from one that reflects his own sensibilities, especially not by Darryl, and lashes out.
I love how Darryl just belittles Michael back, leaving him to his own devices.
The final version of Michael's commercial uses "Chariots of Fire," reminiscient like Donald Trump's bonkers intro at the 2016 Republican National Convention.
BJ Novak wrote this episode, BTW, and I think it's the best one of all of the ones he wrote, which is really saying something because his credits also include the following classics: "Diversity Day", "Sexual Harassment", "The Fire", "Boys and Girls", "Initiation", "Safety Training", "Chair Model", "Prince Family Paper", "Dream Team", "Happy Hour", "Counseling", "Threat Level Midnight", "The List", and "Free Family Portrait Studio".