Surround Mixing problem (HDMI Video Card)

I am struggling to get my setup to support surround mixing (I record on another PC). I am using Cubase 7 in a Home Theater. My PC is Windows 7 with an AMD Raedon HD 6800 Video card which is connected via HDMI to my receiver (Marantz SR5005) which in turn, connects to my 5.1 speakers and HD Projector.

I can bring up Cubase and see and hear (stereo) through my receiver.

However, I cannot seem to get any of my ASIO Drivers to see output buses as anything but HDMI Stereo. I have three ASIO drivers (I forget the exact names): Generic Low latency […]; Direct X […] and ASIO4ALL. None of these provide more than the two stereo channels.

My receiver does not support an input with video from HDMI and audio through another connect, thus, I need to get the Video and 5.1 audio from my video card.

My PC outputs 5.1 sound fine. But the ASIO drivers do not see it. I have tried installing the AMD Catalyst drivers/software. That did not change anything.

I bought this somewhat expensive PC and upgraded to Cubase 7 largely to mix in surround. I have a lot invested and I really want to get this worked out. I greatly appreciate anyone’s help. You will be my hero!

Thanks in advance!

I’m thinking my assumption that my receiver requires that both sound and video come from the HDMI. I am looking through the manual and it seems that I can get my sound from a digital input by reconfiguring the receiver. That may be the better path. Then I will be trying to get a Sound Card to work (ASUS Xonar DG), not a video card…

Any fixes for the video card are still welcome. Otherwise, I will be looking for an optical cable to start over…