How Can I Play Dvd On My 2012 Highlander Car Stereo With Navigation System?

Please, I have two questions:(a) Kindly help me to figure out the brand name for my car stereo with navigation system. The attached pix from the internet is closest to mine in design - except that: (1) The rightside botton "BT" is replaced with a telephone hadset in mine; (2) The leftside botton "BAND" is "DVD" in mine; and (3) The leftside botton "DISC" reads as "BAND" in mine.(b) Each time I insert either audio or video DVD in the palyer, it would display "loading DVD" for a couple of seconds, and eventually reverts back to playing the radio instead. This is very frustrating, and I don't have access to the setup manual; niether do I know the exact brand name of the car stereo/DVD with navigation system. I'll highly appreciate your assistance.