Hooking up a Audio Interface to a desk ?

Hi,
I may be doing something wrong here, I'll try and explain.
I have a V-Studio 20 and a Mackie Pro FX8 desk, at the moment, I'm taking the outputs
at the back of the desk and connecting to my monitors, and then the outputs from my V-Studio 20
I'm connecting to a line in (L & R) on say track 7/8, great I can then use the main slider, and the slider at track 7/8 to control volume, but really I feel I'm just using the desk as a sort of power amp, I want to use the desk to add warmth and some control
to my recordings.
If I then take the other set of outs, and connect to my line L & R inputs in my V-Studio 20, I can't use the main slider
on the desk, and have to use the output level on the V-Studio 20, so I feel again this is not correct.
Anyone help me here please, it's probably me being a bit dumb. Hope this makes sense !!
 
Thanks
John 
  

Hello,
 
I think that I understand what you are trying to do.  I am also going to for the most part agree with CJ. In my humble opinion to really get the impact of OTB mixing, it is probably necessary to move to a higher end analog desk.  These desk usually include summing apparatus and include D/A - A/D conversion hardware.  Some of the names that come to mind on the lower end are, Toft, Oram, Trident.  CJ's price point is speaking to Neve, SSL and other highend studio suppliers. Of personal mention is the Allen and Heath r16 firewire mixture that gives you the "feel" of those aforementioned desks with a built in interface,  at a more easliy reachable price point. 
 
Being a recent owner of the R16, I have to admit that this kind of setup requires a commitment to understanding the equipment, what it does, what it is you want to accomplish and getting the experience to make it happen. But, it is possible to get the basics for learning this kind of mixing for under 2500 dollars. HTH and good luck.