Connecting Wireless Headphones to Directv Model# C51-700 box

I am renting a room in a house that has Directv.  I have Insignia Wireless Headphones that I use to watch TV because I have hearing loss. I've never had to hook them up to Satellite TV before and am encountering problems.  I am using the RCA cable that came with the headphones, plugging them into the docking station, red to red and white to white. Connecting the other end to the red and white connectors on the 3.5 mm-to-RCA adapter cable that purchased.  I connected the other end of the adapter cable into the orange jack on the back of the Directv box, Model# C51-700 which is the only jack that there was to plug into. (SEE PHOTO).  The Directv box does seem to be an older model without the right jacks to hook up headphones.  HELP!!!, I don't like using Closed-Captioning which I've been forced to use. Thank you for any and all advice.