Curtis dvd5029 home theater system only plays...

Question

I have all the connections done correctly and I can only get sound from the left front and center speakers. I can get each speaker to work individually by moving the rca cable to the connection on the back of the dvd player that corresponds with the two speakers that are working, so I know the speakers all work. I am assuming that it is in the setup on the dvd player, but I am not sure.