HDTV audio help

 I have a Vizio HDTV with a cablevision  explorer 4250 HD cable box. I am using the HDMI cable from the box to the TV. I bought a Panasonic SC PT-1050 Home Theater system. I hooked up to the left and right audio out on the cable box to the AUX left + right audio in on the DVD player. When I listen to the TV through the Surround system the volume is VERY limited. When listening to a CD or DVD the sound is awesome. I had the same problem with a Phillips system before this. I returned the system thinking it was the problem but obviously it wasn't. Am I doing something wrong? When I tried the audio out from the TV to the DVD I got no sound at all. Does anyone have any ideas? 
Thanks
gp4free in need of VOLUME!