Days of Future Past: Part 2 - S1-E12
Plot hole: When Gambit charges an object with kinetic energy, it makes a high-pitched sound. When he places a charged card on the arcade game to use as a trap, Wolverine should have heard it, as he possesses a superhuman sense of hearing, especially since Gambit muted the TV. (00:09:28)
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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