Not getting stereo audio with MSI afterburner video captures

[brassplyer]

Using Afterburner 2.3.1 for doing game captures - when I record video in Battelefield Bad Company 2, I only get mono audio recorded when in-game. The audio records as stereo when recording the main screen but once I go in game I only get mono audio recorded, though the audio coming through the speakers is stereo.

Sound card is an Audigy Platinum EX, running XP Sp3.

Any suggestions?

Thanks.