Diddy's lawyers have asked a judge to restrict statements made by potential wintesses and their lawyers outside of court ... citing one grand jury witness in particular who keeps speaking to the press.

The music producer's team filed the documents Sunday ... asking the judge to expedite the process of responding to Diddy's motion for a gag order because one witness -- a man named Courtney Burgess -- has given multiple interviews in recent days.

TMZ caught up with Burgess and his attorney, Ariel Mitchell, outside the courthouse Thursday ... with Mitchell telling us Courtney was called to testify because he has or has seen salcious videos of Diddy and his celebrity friends.

Courtney has made similar claims to other news outlets ... all of which Diddy's team has said are untrue and defamatory.

Diddy's team says -- by not treating such claims as an "extortion scam" -- the government is fueling the online conspiracy fire and is making it impossible for their client to receive a fair trial.

The government has been investigating Diddy for almost a year, his lawyers say, and they know the alleged "Freak Offs" never involved men, minors or parties. Diddy's lawyers specifically cite information in articles from a particular media outlet that has erroneously stated Freak Offs involve "men" and "parties."

As you know ... Diddy was arrested back in September on charges of racketeering conspiracy, sex trafficking by force, fraud or coercion, and transportation to engage in prostitution.