no rear surround

Can't help you much there, this motherboard uses VIA onboard sound chip.

well i have a another 5.1 in the home theater room , but done believe it would solve my issue unless i used the spdif . think its a call manufacturer job

yeh ran through myself

I don't use the onboard sound from my motherboard, so in looking at the graphics in post #4 I'm wondering what is contained in the Stereo Mix tab of the Realtek HD Audio Manager? Is there any way of selecting the channels used for whatever the source material might be?

For example, with the Asus Xonar Audio Center (see below), there is an Audio Channel selection drop down list that you select from according to the source material, i.e. if playing a 5.1 movie you select 6 for the Audio Channel , and 5.1 speakers for Analog Out. If you want 5.1 music from a stereo MP3, you select 2 Channels for the Audio Channel, and 5.1 speakers for the Analog Out (current setting in graphic). So it depends upon what your source is as to what you would select from the Audio Channel drop down list.

Don't know if in the Realtek Audio Manager there might be a similar setting perhaps in the Stereo Mix tab, or elsewhere.

yeh i have a xonar in my home theater system , you have a few more options with xonar

Yes, you do. One reason I went with a dedicated sound card rather than use the onboard as prior to building this system I'd read of too many problems with Realtek onboard.

well my concern is if i go 3 way sli ill need to remove the sound card lol

All in how you like to primarily use your system. I used to be a big gamer, not so much anymore so one graphics card will do; but I do like my music while at the computer hence the Xonar.

Don't know what else to suggest at this point concerning your problem. One of those quirks in the bits that are at times difficult if not impossible to troubleshoot.