Secrets, Not Long Buried - S4-E15
Other mistake: When the group of mutants are listening to Solarr's speech, in one continuous shot of ten of them that lasts at least four seconds, they are all standing completely still, not one of them moving a muscle, blinking or making the slightest adjustment in their facial expressions. (00:17:00)
Secrets, Not Long Buried - S4-E15
Other mistake: At one point after Cyclops ejects from his mini-jet, you can see that he is just floating in midair instead of descending back to the ground. (00:03:15)
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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