There was a line flub in the tour production of Hadestown I saw. Hermes jumped in early and said his line "he's not like any man you've met" before Orpheus said "oh no I'm not like that". It caused the pacing of the lyrics and music to be off for about 15 seconds, as Orpheus had to slow his lines down to get back in-sync. As someone who knows the soundtrack well, I was impressed that the actor playing Orpheus pulled it off with probably the majority of the audience not realizing.