In one of the conversations between Claptrap and Sam, Claptrap will ask about how Sam's voice used to sound different and Sam will reply "Criminals used to laugh at me. They said my voice was too goofy. So I got a voice coach. Now, when I say "Freeze dirtbags !" the dirtbags really freeze.."

This is a reference to actor Bill Farmer who used to provide the voice for Sam and who's also the voice of Goofy for most Disney media.
Contributed by KnowledgeBase
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