Can you elaborate on your issues.
When I use 1 card, its crystal clear - as soon as I add a second card I get horrible hum, whine and crosstalk.
I set up a brand new computer, straight out of the box, with a USB hub and 5 $1 USB sound cards and it worked perfectly.
Then I took a computer that had already been used, it has 4 PCI sound cards in it. I then added a USB hub with 5 $1 USB sound cards. Now this is a "2nd installation", but otherwise I was using the same brand/model hub and sound cards from the same order. Things were goofy ....
To try and trace down the problem I unplugged the USB sound cards and started over. The 4 PCI sound cards "worked". I say worked because they did what they were supposed to do, but each has different sound quality (some have no mic in, some have an input with 2 settings, some have a mic and line in, etc).
I added the hub, OK. I plugged in 1 USB sound card, OK. I plugged in a 2nd USB sound card, OK. Upon plugging in the 3rd USB sound card, other sound cards stopped working correctly. My theory is that the driver for one of the internal cards interferes with this somehow. I could use a different set of USB sound cards, same result. Each card worked individually, and any card would make the rest fail if it was the 3rd one in the hub.
However, when I plugged a 3rd USB card directly into the PC and not via the hub, all is good. Go figure.
My solution is to remove all but one internal PCI sound card and see what happens. But I don't want to take the system out of service (it is streaming two feeds here to RR). So I will wait until I can swap another computer into that spot, then see what I can figure out.
As far as "crystal clear" is concerned; this issue has to do with being able to set the level correctly, and possibly "inheriting" attributes of other sound cards that its hardware does not support. It was not an issue of taking clear audio and making it fuzzy (unless that fuziness was caused by too much or too little audio level).