'Haywire' Star Gina Carano -- YES, My Voice Was Altered

The Gina Carano vocal mystery is OFFICIALLY OVER -- because the rib-cracking MMA fighter has finally admitted that her voice WAS altered for her role in the movie "Haywire."

Carano appeared on a podcast for the "No Holds Barred" MMA blog yesterday ... when she explained why director Steven Soderbergh felt he needed to do some "altering and mixing" to her voice.

Long story short -- Carano says Soderbergh wanted people to believe that Gina and her character are "two completely different entities" ... and felt the vocal change would help.

Carano added, "I'm just honored to be a part of it ... there was a little joke that I was saying that even if [Soderbergh] would have shaved my head and put Bill Clinton as my voice, I would have still done it."