Best USB DAC/Preamp Under $4000 New?

So I would like your help in compiling a list of the best USB DACs under $4K that can also serve as high end preamps with HT bypass. I am thinking that this will be a more desirable route than buying a DAC plus a separate preamp for my music needs. But feel free to weigh in otherwise! Current gear:

Dynaudio Contour S3.4 speakers
McCormack DNA-225 modded driving these
Adcom GFA 2535 (4x90wpc) driving center and rears
Integra DHC 9.9 pre/pro
Source: 1TB external drive playing lossless AIFF files. Signal path; external drive via USB -> laptop. Laptop out via USB -> M-Audio Transit USB, output via Toslink -> pre/pro where D/A conversion happens.

My belief is that the DAC in my pre/pro is a weak link, which is why my 2-channel audio sounds bright and fatiguing. I also believe that the Integra's analog section is sub-par, which would of course reduce the effectiveness of passing the signal after the D/A conversion has been performed by any expensive USB DAC.

So for my 2-channel needs, I need a nice preamp with an HT bypass so that my Integra can still handle my multichannel HT needs, while my music gets handled by some form of DAC/preamp combo. I can go the modded Squeezebox route instead of the USB DAC route. But I would like to skip this and go directly to where I know I will eventually end up anyway...

So far, these are the only contenders in my price range that I can find, for a piece that combines a nice preamp circuitry with HT bypass, plus a high-quality asynchronous USB DAC:

1. Bel Canto DAC3
2. April Music Stello DP-200

Please weigh in with other contenders, or if you believe the better route is to go with a separate DAC and preamp, feel free to weigh in on that (cuz the Ayre QB-9 looks pretty sweet to me, but it is a stand-alone USB DAC. Thanks fellas!