The opportunity to be part of a radio program's live studio audience is becoming a bygone treat. There are fewer and fewer chances to have the action unfold right in front of your eyes and ears, with your own oohs, aahs and guffaws becoming part of the broadcast. Thankfully the heartwarming stage play Christmas on the Air takes you back to that special time and puts you back in the action. The year is 1949, and station director Percival B. Frank and the employees of CKOS Radio are broadcasting their annual Christmastime show, complete with music, classic holiday songs and cues for the audience to follow. Treat the whole family to this nostalgic show at Stoneham Theatre.