SPDIF Passthrough from onboard audio

[ajocius]

Hi,

 

I have ASUS P5AD2-E Premium motherboard with integrated C-Media audio chip CMI 9980. I would like to use optical audio out socket to get unprocessed digital audio signal to my AV receiver, that should process the signal and distribute to the right channels. However I do not find an option in C-Media Audio 3D Configuration window to select. The only time I get some audio out is when I select Digital Audio Live button, but I believe this option is actually process the siganl and sends out analog signal to AV Receiver via optical cable. I come to that conclusion, since I can control sound volume from PC. This is not an option if I get digital sound from other sources. In those cases I can only regulate sound on my AV receiver, since that is where sound is processed and amplified.

 

Any help?

Endret 2. oktober 2006 av ajocius

[ajocius]

Hi added three screenshots to ilustrate what I am talking about. One screenshot is from C-Media 3D Audio configuration and two others are from WinDVD v6, where I can open files with DTS or DD sound and play back. I can get 5.1 sound if I direct sound through Audigy 2 soundcard to my 5.1 speaker setup for PC. However, when I direct sound to the onboard C-Media card (which has optical out jack), I do not get an option to pass S/PDIF out.

 

I have AC3 filter installed on PC, could that do decoding and passing out analog signal?

 

I also tried to open files with winamp which has Winamp AC3 decoder. Once I sent signal out to my AV receiver, I finaly got that digital noice through my loudspeakers. I thought I finally got digital signal out, but then I am bewildered on why is it not decoded by my Yamaha RX-V2600 receiver, that is capable to decode both DTS and DD?

[ajocius]

Another alternative for me would be to use digital coax cable thatt my integrated C-Media audio card has. I just don’t see logical explanation on why would that work. And I do not have digital cable long enough to try. Third alternative would be to connect an Audigy 2 soundcard that I have in PC connected through PCI slot on motherboard. I heard that one can pass through digital audio through one of its minijacks. I haven’t chose this alternative earlier as I use Audigy to send sound to my 5.1 loudspeaker’s close to PC. I understand and can not have that AND digital out at the same time . So basically I would need to swith digital out off, when I want to use loudspeakers close to PC. I would then need to swith back to digital audio out, when I want to listen through receiver and loudspeakers in home cinema room. That is why, I would really like to make it work through digital audio cables (optical as a first choice, as I already purchased cable  ).

 

What do I do wrong there?