Voice *actors* act. It is in the name. The voice they perform in is not their usual voice. A good voice actor can do dozens of different characters. If you hire a voice actor to impersonate someone else's voice, that is infringement. Bette Midler vs Ford, Tom Waits vs Frito Lay are the two big examples of court cases where a company hired voice actors to impersonate a celebrity for an ad, and lost big in court.
Believe it or not, these issues have been around for decades, and have been well settled for nearly as long.