No sound on SD TV channels

[woddog]

TV-Server Version: 1.0 RC1
MediaPortal Version: 1.0 RC1
MediaPortal Skin: blue two wide
Windows Version: vista SP1
CPU Type: E8200
HDD:
Memory: 4GB
Motherboard: GA-G33M-DS2R
Video Card: EN8500GT silent
Video Card Driver:
Sound Card: onboard ALC889a
Sound Card AC3:
Sound Card Driver: Gigabyte R1.87
1. TV Card: Fusion HDTV DVB-T plus
1. TV Card Type:
1. TV Card Driver:
2. TV Card:
2. TV Card Type:
2. TV Card Driver:
3. TV Card:
3. TV Card Type:
3. TV Card Driver:
4. TV Card:
4. TV Card Type:
4. TV Card Driver:
MPEG2 Video Codec:
MPEG2 Audio Codec:
h.264 Video Codec:
Satelite/CableTV Provider:
HTPC Case:
Cooling:
Power Supply:
Remote:
TV: PT-AX100 projector
TV - HTPC Connection: DVI-HDMI

Hi, Weird problem here.
on Australian DVB-T TV I can't seem to get any sound at all on the SD channels. HD channels are perfect. I have changed from the standard decoder to AC3filter, played with AC3filter settings but can't seem to fix the problem. Also changed from default directsound to S/PDIF etc
It is going to the reciever via coax S/PDIF.



Found out after trying every single setting in AC3filter that I needed to have MPEG audio (passthrough) unchecked. assuming the receiver can't decode it?

So confusing!