Computer from headphone jack to aux only plays out of right speaker on 5.1 system?

Alright so heres my problem - i have a headphone jack hooked up to my aux on my dvd player (which connects to my surround sound) the dvd player and surround sound system is a phillips or whatever. anyways, i have it connected and it plays loudly out of the front right speaker, the sub plays but is quiet, the front left is the same as the sub and the two back speakers as well as the center are silent. the system works well on my xbox (from the xbox to the tv via hdmi cable, then RW to the tv section of the dvd player) i also have this same issue when doing a similar connect from the laptops headphone jack. any ideas would be appreciated thanks ^_^