Probably not as much an accurate portrayal of what is was like to work at an FM rock station in the 70's, this is most likely what most music obsessed teenagers during that time period thought it was like. FM was released at a time when record companies were moving about a gazllion albums a year and the last visages of underground FM radio was slowly being ground under the corporate heel (which is the main point of this film's plot). Like most movies of this ilk (although its does have some more serious overtones), FM is not not so much an accurate picture of the music/radio industry at the time, but an entertaining nostalgia trip that in its own audience friendly way does capture the heady feel of an entertainment industry that truly felt like the sky was the limit.
Produced by Universal and directed by cinematographer John Alonzo (CHINATOWN) it was released in the spring of 1978 where put up against the mega-hits of GREASE and the re-released PG version of SATURDAY NIGHT FEVER it faded away quickly. The subsequent soundtrack double album, which for better or worse is a virtual time machine of late 70's FM radio, went on to become a sizable hit complete with the soon to be insufferable Steely Dan title track that for obvious reasons was played ad nauseam on FM radio at the time (complete with a dubbed in AM version for that radio format).
Michael Brandon (who had starred in Dario Argento's FOUR FLIES ON GRAY VELVET) plays Jeff Dugan program director at fictional Los Angeles FM station QSKY (although allegedly based upon the real life L.A. station KMET) who finds himself under increasing pressure from the corporate big-wigs to try and reign his free form radio format. The main thrust of this comes in the form of some "hip" army recruiting spots (promoted by a hilarious James Keach as a stoned army Lt.) that Dugan is being forced to air.
By far the best part of the movie is the cast of QSKY DJ's that include Martin Mull as Eric Swan (the popular ego driven jock), Clevon Little's Prince (the hip late night DJ), Alex Karras as Doc Holiday (who's career is sadly fading away) and best of all Eileen Brennan as "Mother", a burned out ex-hippie who holds her job and her audience in equal contempt. Brandon as a leading man seems a bit flat, but in all fairness this is most due to the writing, as his character balances out the maniacal supporting cast.
The movie also features two live performances by Linda Ronstadt and Jimmy Buffet, both of which stop the plot dead in its tracks, but were heavily promoted in the film's marketing (a bit of fair disclosure here - I enjoy Ronstadt's early country rock stuff, but despise Jimmy Buffet) and an interview segment with Tom Petty. Long time Los Angeles residents should get a kick out of the segment filmed in and around Tower Records Sunset Blvd. location (complete with an album signing by REO Speedwagon).
In spite of its lack of commercial success it can be looked at as a predecessor to WKRP (which premiered in the fall of 1978). FM had brief release on DVD, but quickly went out of print (and now commands high prices on the secondary market). Like AMERICAN HOT WAX from the same year, its likely tied up in music publishing rights hell.