WinFast DTV2000H Audio Issue

[Scruff]

AMD 7750 Dual Core, ASUS M2N68-AM Plus, 2GB RAM, Onboard Realtek HD Audio, WinFast DTV2000H TV Card, Windows XP SP2

This is a fresh installation and SP3 is not an option - it doesn't fix the problem, it only breaks other things.

Audio is fine in all programs except WinFast PVR2.

WinFast PVR2 only shows an option in the configuration for Stereo, and not 5.1 or Surround.

When watching TV, I get sound from all speakers on channels transmitting mpg audio (stereo), but only the front speakers on channels transmitting AC3 (5.1 - HD channels).

If I start recording, I hear full surround sound, and it goes back to the front speakers when I stop recording.

K-Lite codec pack is installed (playback essentials without player) and AC3 Filter is installed, but none of these load when watching TV. I suspect that it's a problem with the PVR software because it doesn't list any surround option in it's config page. What is confusing though, is that it switches to surround by itself when recording.

Anyone have any ideas as to how to fix this?