A:Answer This TV does not have an RCA "In" or RCA "out" jack. It has composite audio out (a red connector and a white connector), which you can connect to the audio "in" on your audio receiver. Better to connect your subwoofer to your audio receiver, and choose "external speakers" or "external sound" on the TV's setup menu under "Sound." Or even easier, buy a soundbar which has a built-in subwoofer. Insignia probably makes one, or Vizio, Samsung, or LG. Check out soundbars on the Best Buy website.