"PREVIEW" PREMIERES: Classical music station WGMS (570 AM, 103.5 FM) debuts "Washington Music Preview" Monday at 8:05 p.m., immediately preceding the National Symphony Orchestra concert broadcast. Music critic Paul Hume and WGMS music director Calvin Le Compte, cohosts of the 55-minute show, will discuss major upcoming music events and selected works and will interview classical-music notables.

STAR WARS STRIKES BACK: National Public Radio's popular 13-part adaptation of "Star Wars," featuring the voices of original stars Mark Hamill (Luke Skywalker) and Anthony Daniels (C3P0), returns to WETA-FM (90.9) beginning Wednesday at 4:30 p.m.

CURRENTS: Disc jockey Lisa Kay, who held the 10 p.m.-to-2 a.m. shift on WPGC-FM, has been replaced temporarily by weekend deejay Max Wolf. Kay, a three-year veteran of WPGC, was given no reason for her dismissal. Program director Jerry Steele refused to comment . . . WQRA-FM (94.3) has picked up ABC's syndicated series "Musical!," a three-hour stereo radio salute to Broadway and Hollywood musicals, with host Chuck Southcott and special guests. "Musical!" airs Sundays, 7 to 10 p.m. . . . NPR has received a $325,000 grant from the National Endowment for the Humanities for a 13-part radio series, "Faces, Mirrors, Masks: 20th-Century Latin American Writers." The series will feature interviews with Argentina's Jorge Luis Borges, Mexico's Carlos Fuentes, Peru's Mario Vargas Llosa and 1982 Nobel Prize winner Gabriel Garcia Marquez of Colombia. No broadcast date has been set . . . NPR also walked off with six 1981 Armstrong Awards for excellence and originality in radio broadcasting. . . . It may not be as earth-shaking as "War of the Worlds," but it should provide a chill or two: The second annual "Halloween Night Radio Broadcast, Live From the Magic Castle" will air Sunday, 10 p.m. to midnight, on WASH-FM (97.1). Guests include actors Jack Palance and John Carradine . . .