The Winterfilm Collective (listed as Winterfilm, Inc. in the credits to the film "Winter Soldier") consisted of Fred Aronow (cinematographer), Nancy Baker (editor), Joe Bangert (member of Vietnam Veterans Against the War), Rhetta Barron (editor), Robert Fiore (cinematographer), David Gillis (cinematographer), David Grubin, Jeff Holstein (cinematographer), Barbara Jarvis (editor), Algis "Al" Kaupas (sound mixer), Barbara Kopple, Mark Lenix (another VVAW member), Michael Lesser (cinematographer), Nancy Miller (sound mixer), Lee Osborne (sound mixer), Lucy Massie Phenix (editor), Roger Phenix (sound mixer), Benay Rubenstein (editor), Rusty Sachs (VVAW member), and Michael Weill (editor).
A utility sound technician, also referred to as sound assistant, sound maintenance or cableperson is an assistant to both the production sound mixer and the boom operator on a film or television set.
 Although sometimes the utility pulls cable, he or she is more than just a cableperson.
 The utility is a jack of all trades, assisting in setting up, operating and maintaining the running order of equipment, often acting as a second boom operator, or even second mixer, and also repairing and servicing equipment such as cables and hardware as necessary.
 As both mixer and boom operator(s) may be busy with their tasks at any given time, the utility may also apply or adjust personal microphones or actors' wireless transmitters, may move microphones or assist in running cables, and may liaise with other departments on issues such as noise minimisation and set lockdown.
Willie D. Burton is an American production sound mixer.
 His career has spanned four decades and has included films such as "The Shawshank Redemption", "Se7en", and "Indiana Jones and the Last Crusade".
 Burton has been nominated for the Academy Award for Best Sound or Best Achievement in Sound Mixing a total of seven times, winning twice; he has been nominated for two BAFTA Film Awards for Best Sound, winning once; and he was nominated for one Emmy Award for Outstanding Achievement in Film Sound Mixing for his work on "Roots".
Walt Martin (April 8, 1945 – July 24, 2014) was an American production sound mixer.
 He was nominated for Academy Awards in the category Best Sound for the 2006 film "Flags of Our Fathers" and the 2014 film "American Sniper".
 He worked on more than 70 films.
 He died of vasculitis on July 24, 2014, aged 69.
 His final film, "American Sniper", was released posthumously.
A production sound mixer, location sound recordist, location sound engineer or simply sound mixer is the member of a film crew or television crew responsible for recording all sound recording on set during the filmmaking or television production using professional audio equipment, for later inclusion in the finished product, or for reference to be used by the sound designer, sound effects editors, or foley artists.
 This requires choice and deployment of microphones, choice of recording media, and mixing of audio signals in real time.
Ron Judkins (born 1953) is an American production sound mixer and writer-director.
 He has won two Academy Awards for Best Sound and has been nominated for another three in the same category.
 He is also the winner of the BAFTA Award for Best Sound for "Schindler's List" in 1996.
 Judkins directed his first feature film, "The Hi-Line" in 1998, and the project premiered in the Dramatic Competition at the 1999 Sundance Film Festival.
David Lewis Yewdall (October 30, 1950 – July 4, 2017) was an American production sound mixer.
 He worked with Roger Corman on "Battle Beyond the Stars" and as the co-supervising sound editor on "Talvisota".
 He published a book about the profession in 2007, "Practical art of motion picture sound", which was called a "must-read for all students of film."
 In 1996, he became a member of the board of NightPro Technologies Inc (NTI), a sound production company from Provo, Utah.
 He taught editing and sound at the University of North Carolina School of the Arts
Stephen Tibbo is a sound mixer, who has worked in "American Pie 2", "Kiss Kiss Bang Bang", in addition to television shows including "Modern Family", "Ghost Whisperer", and "Life".
 In addition, Tibbo did webisodes for the show "Childrens Hospital", which won an Emmy".
 Since the early 90's, Stephen Tibbo has "worked in both production and post production" and in "2007 Stephen built his own stage to do ADR and to mix film and television projects".
Anand Krishnamoorthi is an Indian film sound designer, sound editor and production sound mixer.
American Pie 2 is a 2001 American sex comedy film and the sequel to the 1999 film "American Pie" and the second film in the "American Pie" film series.
 It was written by Adam Herz and David H. Steinberg and directed by James B. Rogers.
 The film picks up the story of the five friends from the first film as they reunite during the summer after their first year of college.
 It was released in the United States on August 10, 2001, and grossed over $145 million in the US and $142 million overseas on a budget of $30 million.
 It was followed by another sequel, "American Wedding".

Question: What sex comedy film has Stephen Tibbo been a sound mixer for?
Answer: American Pie 2