I am capturing from Satellite payTv in Australia. Audio is captured by the the soundcard on the standard "Line in" interface, from my Yamaha Home Theatre system.

I cant be certain about the technical details of the satellite broadcast except that the sound quality is very good and is in Surround Sound.

I am capturing using Virtual Dub, and audio at the standard "CD Quality" setting 172kbps and 44000k

after capturing, processing, and converting to SVCD format, the sound from the rear effect speakers contains a distorted and echo-ish but low volume sound, based on what should be heard from the front.
This is even worse when capturing an old TV show that is obviously in mono. I have tried some tricks with Besweet but it didnt work.

Is anyone capturing and experiencing this kind of sound problem?