I have similar gear, Virtue Two.2-Power Amp only, Piano M1, Grant DAC-09 as a pre-amp and DAC, VAIO Laptop running SB server, Squeezebox Touch lighting up some JBL's.
Are you feeding the DAC with a USB output from the laptop??
I was actually thinking about Grants new Yuolong SABRE DAC keeping the DAC-09 as pre-amp or having a passive pre-amp built to replace it-adding a remote volume control.
I'd look at little stuff now-you have an excellent setup right now- maybe convert the USB signal to COAX or Optical and feed the DAC that way as it might be cleaner sounding. Batteries would be next to look at also.....What I did - and amazingly it worked out fantastic. I tried to eliminate as much crap in the signal, to make it cleaner and have a blacker background. The converter box I mentioned earlier would only work for you if it cleans up the USB signal, batteries would be huge, upgrade power supplies wherever you can--you'll hear that, I tried not to, but the difference was way too obvious.
Read stuff in Bolder Cable's circle and see if it helps you maybe change out power supply to the Dell or anything else that you can.....not super expensive but I would almost guarantee you'll hear a nice difference.
