The Nightmare Before Christmas (lost original Vincent Price audio of Disney stop-motion animated film; early 1990s)
From The Lost Media Wiki
The Nightmare Before Christmas is a 1993 stop-motion film directed by Henry Selick, produced by Tim Burton and Denise Di Novi and written by Caroline Thompson and Michael McDowell. It was released by Walt Disney Pictures under their Touchstone Pictures banner.
The movie originally had Vincent Price as the voice of Santa Claus, but due to his health declining after his wife's death, his voice became frail and weak and the record tracks featuring his vocal performance were deemed unusable, leading to the role being recast, much to Selick's regret.
So far the audio featuring Price's voice work has never been publicly heard and it's unknown as to whether or not either Selick or Disney are even still in possession of the recordings.