Basically, if you re-read the manual that came with the Duo Capture, you will be set up and ready to go.  It is not difficult to get the  Roland Octa - Capture, Duo- Capture, or Tri - Capture working configured and working with Sonar.
 
Is this the Duo -Capture EX or Duo - Capture mk2?  Which one are you using? 
 
Just re-read the manual and follow each and every step, and it will work.  Don't miss the part about installing the drivers.
 
DUO Capture EX Manual  /   DUO Capture mk2 Manual

If vwillis007 returns, I bet he/she/it/they will be shocked to find that the thread has already turned a page without any additional participation 

The forums continue on even if the OP doesn't return to participate. 
 
That's the the nature of the forums!! 
 
 

At least he didn't mention Reaper. That usually goes hand in hand with the 1 post, "SONAR sucks" motif.

But the word choice in the title made the thread go "Hot" already... funny how that works... sorta like "forum rubbernecking"

Anderton
At least he didn't mention Reaper. That usually goes hand in hand with the 1 post, "SONAR sucks" motif.

If he is having trouble learning Sonar, Reaper will beat him silly. 

To the pessimist, Sonar is a monstrosity.
To the optimist, Sonar is fully featured. 
To the realist Sonar is great, but still needs improvement.
 
Just goes to show....you can please some of the people some of the time, but you can't please ALL the people ALL the time.
 
 

I taught my self to read music when I was 14.
I wanted to play guitar.
 
Started to read a few manuals and work books; after an HOUR I  threw the books into a trash bin
and went outside to play ball.
I never made it to the court. Something welled up in me and I turned around,
marched back home and locked myself in my bedroom until I knew how to read music.
 
I am sure the OP is experiencing SOME measure of this...
He/She is probably shedding.
 
Mel

John

Anderton
At least he didn't mention Reaper. That usually goes hand in hand with the 1 post, "SONAR sucks" motif.

If he is having trouble learning Sonar, Reaper will beat him silly. 

 
LOL, Hey!!! I LIKE Reaper;
John is right tho... if the OP thinks Sonar's learning curve is steep...
I stopped using it as much because it seemed to turn into such a science project.
But if you have some kinda crazy setup you want, Reaper bends like pretzel.
 
Mel 

If the OP thinks Sonar is a monstrosity, then may be he/she will want to use Audacity.  It's free, it's as simplistic as it comes and it will still get the job done.
 
But he/she still still have to read the manual!!!