Do you have it set to play PLII (Pro Logic II)?
Since the tv doesn't have a digital output for audio (it doesn't, does it?), the best you'll get from it is PLII......... Are you watching cable, satellite or OTA?
Double check your settings in the receiver's setup menus, and make sure the tv input is set for analog, instead of digital (really should be from factory). If you turn off surround, do you get it out of the two front main speakers?
Double check the manual's pages for hooking up the tv, and go step by step. Take your time, and see if you can't get it set right. It sounds like the settings isn't quite right.
Good luck! Keep us posted?