'Til Death Do Us Part: Part 1 - S2-E1
Audio problem: When the Friends of Humanity are approaching the mutant that looks like a werewolf, they are saying "No more mutants," and none of them are pressing their lips together to produce the "M" sounds when saying "more" and "mutants." (00:08:37)
Answer: Chris Potter, the original Gambit voice actor, did indeed quit the role in the 4th season. His last episode was The Phalanx Covenant Part 1 so it seems reasonable that Fox would limit the use of the character even though it was recast. It doesn't appear that Potter left the role due to animosity, he stated in an interview that he wished to play Gambit in the first live action X-Men film.
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