Very low volume on center speaker

[krbaugh]

I have hauppauge 1600 and a hauppauge 500
The sound is fine with the analog tuners
but on the high def channels i get no center channel
for example I get the sound of the game but no announcers??

This is driving me crazy I am using t he latests drivers for the tunners and sagetv 6.6.2

[MitchSchaft]

How is your sound set up?

[krbaugh]

My sound comes out of Pc into the tv then into the stereo
If I don't use the Stereo and play the TV speakers I get the same results very low dialog and very loud background I have to turn the volume way up on the High def and down low on the analog.

In Sagetv the sound is set to
Audio render is set to default ( have tried many combinations)
audio decoder is set to ac3 (I have tried several other decoders)

The Dell soundmax card is set to surround I have also tried other settings

[krbaugh]

Ok this turns out to be the video decoder no the audio one
If it is set to the nvidia video decoder i got the strange audio
if I set it to my intervideo decoder the sound is correct however my
computer is pegged at a very high cpu usage and the remote hardly responds

Why would the video decoder affect my sound??