IP35-Pro and Optical In

[UnFeoMateo]

I have an IP35-Pro and want to hookup my ps3 to the optical in and play through my klipsch speakers. The problem is the ip35 won't play from the optical in using the analog speakers.

Is there a better soundcard I can get to solve my problem or is there an optical out to analog converter I can buy? any help would be appreciated.

Thanks

-IP35-Pro
-Windows Vista