Dr. Conrad Murray has outdone himself ... this time sending an audio message to Paris Jackson, telling her he'd like to help her figure out what's eating her.

Murray used a pay phone to send what he calls a "letter" to Paris, telling her "I don't know if there's anything to do to solve your pain," adding, "I'm here for you."

The message is bizarre ... Murray also uses the title of a Jackson song, "You Are Not Alone."  He also uses verses from "Ain't No Mountain High Enough" and "You've Got a Friend."

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