I just recently upgraded my HT to 7.1 by buying a sony strdg720 receiver and polk psw10 subwoofer. I hooked my ps3 to the receiver with hdmi and did the automatic sound format selection. When ever I am playing a cd, mp3, or anything in stereo, the subwoofer sounds great. However when I play a dvd or bluray in surround sound, the bass is very weak and sometimes almost non existent. The subwoofer dosent even emit sound playing Rockband!!

I tried hooking the ps3 up with optical connection and I dont have this problem at all, but the whole reason I bought these components was to have 7.1 audio.

Are there certain sound formats I should turn off in the ps3 options or does anyone know why I would have this problem? I am pretty frustrated since I just spent a bunch of money and now I have no bass. Thanks for any help!

here are some pics that might help:
http://img7.imageshack.us/img7/2219/strdg720back.jpg (http://img7.imageshack.us/my.php?image=strdg720back.jpg)

http://img7.imageshack.us/img7/4086/psw10back.jpg (http://img7.imageshack.us/my.php?image=psw10back.jpg)

Problem fixed!! after several hours of tweaking every option imaginable, I finally read every word in my receiver's manual. It turns out that the front speakers were set at "large" instead of "small" meaning they reproduced the bass instead of the subwoofer. Its a wonder what reading the manual will actually do!

Awesome you figured it out. I have the same sub, excellent for the money.

Always great when you can figure out what problems you're having without resorting to paying for a repairman. :D I had a friend who's LCD TV crapped out on her, but she was able to look up what could be wrong and simply replaced a capacitor in the power supply and got it working again.

When I was building my speaker system, I had issue with the tweeter in one of the front main speakers. Was driving me nuts. Finally, I went and de-soldered an inductor from the crossover and then resoldered it to the x-over. Boom! Everything was now working. Nothing like hearing great sound coming out of your system. (Rock Band sounds INSANE when I play it. :D )