 Bagdasarian and his wife, Janice Karman, had always voiced the chipmunks since they revived the franchise; however, for the film, they were replaced by younger, more well-known actors for marketing reasons.For recording, the chipmunk voice actors spoke their lines slowly to be sped up to normal speed in post-production; McCartney described it as a "tedious process," where "it could take 40 takes for one line.