Days of Future Past: Part 1 - S1-E11
Audio problem: When Bishop is saying "They treat the rest of us just fine," his mouth is not moving for the last two words. (00:04:53)
Days of Future Past: Part 1 - S1-E11
Audio problem: When Beast says to Gambit "Though I am always in haste, I am never in a hurry," his mouth is completely closed for most of the line. (00:11:30)
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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